Head of
"Oncogenetics"
Zhusina
Yulia Gennadievna
Graduated from the Pediatric Faculty of Voronezh State Medical University. N.N. Burdenko in 2014.
2015 - internship in therapy at the Department of Faculty Therapy of VSMU named after. N.N. Burdenko.
2015 - certification course in the specialty “Hematology” at the Hematology Research Center in Moscow.
2015-2016 – therapist at VGKBSMP No. 1.
2016 - the topic of the dissertation for the degree of Candidate of Medical Sciences “study of the clinical course of the disease and prognosis in patients with chronic obstructive pulmonary disease with anemic syndrome” was approved. Co-author of more than 10 published works. Participant of scientific and practical conferences on genetics and oncology.
2017 - advanced training course on the topic: “interpretation of the results of genetic studies in patients with hereditary diseases.”
Since 2017, residency in the specialty “Genetics” on the basis of RMANPO.
Head of
"Genetics"
Kanivets
Ilya Vyacheslavovich
Kanivets Ilya Vyacheslavovich, geneticist, candidate of medical sciences, head of the genetics department of the medical genetic center Genomed. Assistant at the Department of Medical Genetics of the Russian Medical Academy of Continuing Professional Education.
He graduated from the Faculty of Medicine of the Moscow State Medical and Dental University in 2009, and in 2011 – a residency in the specialty “Genetics” at the Department of Medical Genetics of the same university. In 2017, he defended his dissertation for the scientific degree of Candidate of Medical Sciences on the topic: Molecular diagnostics of copy number variations of DNA sections (CNVs) in children with congenital malformations, phenotypic anomalies and/or mental retardation using high-density SNP oligonucleotide microarrays.”
From 2011-2017 he worked as a geneticist at the Children's Clinical Hospital named after. N.F. Filatov, scientific advisory department of the Federal State Budgetary Institution “Medical Genetic Research Center”. From 2014 to the present, he has been heading the genetics department of the Genomed Medical Center.
Main areas of activity: diagnosis and management of patients with hereditary diseases and congenital malformations, epilepsy, medical and genetic counseling of families in which a child was born with hereditary pathology or developmental defects, prenatal diagnosis. During the consultation, clinical data and genealogy are analyzed to determine the clinical hypothesis and the necessary amount of genetic testing. Based on the results of the survey, the data are interpreted and the information received is explained to the consultants.
He is one of the founders of the “School of Genetics” project. Regularly gives presentations at conferences. Gives lectures for geneticists, neurologists and obstetricians-gynecologists, as well as for parents of patients with hereditary diseases. He is the author and co-author of more than 20 articles and reviews in Russian and foreign journals.
Area of professional interests is the implementation of modern genome-wide research into clinical practice and interpretation of their results.
Reception time: Wed, Fri 16-19
Head of
"Neurology"
Sharkov
Artem Alekseevich
Sharkov Artyom Alekseevich– neurologist, epileptologist
In 2012, he studied under the international program “Oriental medicine” at Daegu Haanu University in South Korea.
Since 2012 - participation in organizing the database and algorithm for interpreting genetic tests xGenCloud (http://www.xgencloud.com/, Project Manager - Igor Ugarov)
In 2013 he graduated from the Pediatric Faculty of the Russian National Research Medical University named after N.I. Pirogov.
From 2013 to 2015, he studied at a clinical residency in neurology at the Federal State Budgetary Institution "Scientific Center of Neurology".
Since 2015, he has been working as a neurologist and researcher at the Scientific Research Clinical Institute of Pediatrics named after Academician Yu.E. Veltishchev GBOU VPO RNIMU im. N.I. Pirogov. He also works as a neurologist and a doctor in the video-EEG monitoring laboratory at the clinics of the Center for Epileptology and Neurology named after. A.A. Kazaryan" and "Epilepsy Center".
In 2015, he completed training in Italy at the school “2nd International Residential Course on Drug Resistant Epilepsies, ILAE, 2015”.
In 2015, advanced training - “Clinical and molecular genetics for medical practitioners”, RDKB, RUSNANO.
In 2016, advanced training - “Fundamentals of molecular genetics” under the guidance of a bioinformatician, Ph.D. Konovalova F.A.
Since 2016 - head of the neurological direction of the Genomed laboratory.
In 2016, he completed training in Italy at the school “San Servolo international advanced course: Brain Exploration and Epilepsy Surger, ILAE, 2016”.
In 2016, advanced training - “Innovative genetic technologies for doctors”, “Institute of Laboratory Medicine”.
In 2017 – school “NGS in Medical Genetics 2017”, Moscow State Research Center
Currently conducting Scientific research in the field of genetics of epilepsy under the guidance of Professor, MD. Belousova E.D. and professor, doctor of medical sciences. Dadali E.L.
The topic of the dissertation for the degree of Candidate of Medical Sciences “Clinical and genetic characteristics of monogenic variants of early epileptic encephalopathies” has been approved.
The main areas of activity are the diagnosis and treatment of epilepsy in children and adults. Narrow specialization – surgical treatment of epilepsy, genetics of epilepsy. Neurogenetics.
Scientific publications
Sharkov A., Sharkova I., Golovteev A., Ugarov I. “Optimization of differential diagnosis and interpretation of genetic testing results using the XGenCloud expert system for some forms of epilepsy.” Medical Genetics, No. 4, 2015, p. 41.
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Sharkov A.A., Vorobyov A.N., Troitsky A.A., Savkina I.S., Dorofeeva M.Yu., Melikyan A.G., Golovteev A.L. "Epilepsy surgery for multifocal brain lesions in children with tuberous sclerosis." Abstracts of the XIV Russian Congress "INNOVATIVE TECHNOLOGIES IN PEDIATRICS AND CHILDREN'S SURGERY." Russian Bulletin of Perinatology and Pediatrics, 4, 2015. - p.226-227.
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Dadali E.L., Belousova E.D., Sharkov A.A. "Molecular genetic approaches to the diagnosis of monogenic idiopathic and symptomatic epilepsies." Thesis of the XIV Russian Congress "INNOVATIVE TECHNOLOGIES IN PEDIATRICS AND CHILDREN'S SURGERY." Russian Bulletin of Perinatology and Pediatrics, 4, 2015. - p.221.
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Sharkov A.A., Dadali E.L., Sharkova I.V. “A rare variant of early epileptic encephalopathy type 2 caused by mutations in the CDKL5 gene in a male patient.” Conference "Epileptology in the system of neurosciences". Collection of conference materials: / Edited by: prof. Neznanova N.G., prof. Mikhailova V.A. St. Petersburg: 2015. – p. 210-212.
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Dadali E.L., Sharkov A.A., Kanivets I.V., Gundorova P., Fominykh V.V., Sharkova I.V. Troitsky A.A., Golovteev A.L., Polyakov A.V. A new allelic variant of myoclonus epilepsy type 3, caused by mutations in the KCTD7 gene // Medical Genetics.-2015.- Vol.14.-No.9.- p.44-47
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Dadali E.L., Sharkova I.V., Sharkov A.A., Akimova I.A. "Clinical and genetic features and modern methods diagnosis of hereditary epilepsies". Collection of materials “Molecular biological technologies in medical practice” / Ed. Corresponding member RAIN A.B. Maslennikova.- Issue. 24.- Novosibirsk: Akademizdat, 2016.- 262: p. 52-63
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Belousova E.D., Dorofeeva M.Yu., Sharkov A.A. Epilepsy in tuberous sclerosis. In "Brain diseases, medical and social aspects"edited by Gusev E.I., Gekht A.B., Moscow; 2016; pp.391-399
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Dadali E.L., Sharkov A.A., Sharkova I.V., Kanivets I.V., Konovalov F.A., Akimova I.A. Hereditary diseases and syndromes accompanied by febrile seizures: clinical and genetic characteristics and diagnostic methods. //Russian Journal of Child Neurology.- T. 11.- No. 2, p. 33- 41. doi: 10.17650/ 2073-8803-2016-11-2-33-41
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Sharkov A.A., Konovalov F.A., Sharkova I.V., Belousova E.D., Dadali E.L. Molecular genetic approaches to the diagnosis of epileptic encephalopathies. Collection of abstracts “VI BALTIC CONGRESS ON CHILD NEUROLOGY” / Edited by Professor Guzeva V.I. St. Petersburg, 2016, p. 391
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Hemispherotomy for drug-resistant epilepsy in children with bilateral brain damage Zubkova N.S., Altunina G.E., Zemlyansky M.Yu., Troitsky A.A., Sharkov A.A., Golovteev A.L. Collection of abstracts “VI BALTIC CONGRESS ON CHILD NEUROLOGY” / Edited by Professor Guzeva V.I. St. Petersburg, 2016, p. 157.
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Article: Genetics and differentiated treatment of early epileptic encephalopathies. A.A. Sharkov*, I.V. Sharkova, E.D. Belousova, E.L. Yes they did. Journal of Neurology and Psychiatry, 9, 2016; Vol. 2doi: 10.17116/jnevro 20161169267-73
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Golovteev A.L., Sharkov A.A., Troitsky A.A., Altunina G.E., Zemlyansky M.Yu., Kopachev D.N., Dorofeeva M.Yu. " Surgery epilepsy in tuberous sclerosis" edited by Dorofeeva M.Yu., Moscow; 2017; p.274
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New international classifications of epilepsies and epileptic seizures of the International League Against Epilepsy. Journal of Neurology and Psychiatry. C.C. Korsakov. 2017. T. 117. No. 7. P. 99-106
Head of Department
"Genetics of predispositions"
biologist, genetic consultant
Dudurich
Vasilisa Valerievna
– head of the department “Genetics of predispositions”, biologist, genetic consultant
In 2010 – PR specialist, Far Eastern Institute of International Relations
In 2011 – Biologist, Far Eastern Federal University
In 2012 – Federal State Budgetary Institution Research Institute of Physics and Chemistry, FMBF of Russia “Gene diagnostics in modern medicine”
In 2012 – Study “Introduction of genetic testing into a general clinic”
In 2012 – Professional training “Prenatal diagnosis and genetic passport - the basis of preventive medicine in the age of nanotechnology” at the D.I. Ott Research Institute of AG, Northwestern Branch of the Russian Academy of Medical Sciences
In 2013 – Professional training “Genetics in clinical hemostasiology and hemorheology” at the Bakulev Scientific Center for Cardiovascular Surgery
In 2015 – Professional training within the framework of the VII Congress of the Russian Society of Medical Genetics
In 2016 – School of Data Analysis “NGS in Medical Practice” of the Federal State Budgetary Institution “MGSC”
In 2016 – Internship “Genetic counseling” at the Federal State Budgetary Institution “MGNC”
In 2016 – Participated in the International Congress on Human Genetics in Kyoto, Japan
From 2013-2016 – Head of the Medical Genetics Center in Khabarovsk
From 2015-2016 – teacher at the Department of Biology at the Far Eastern State Medical University
From 2016-2018 – Secretary of the Khabarovsk branch of the Russian Society of Medical Genetics
In 2018 – Participated in the seminar “Reproductive Potential of Russia: Versions and Counterversions” Sochi, Russia
Organizer of the school-seminar “The Age of Genetics and Bioinformatics: Interdisciplinary Approach in Science and Practice” - 2013, 2014, 2015, 2016.
Work experience as a genetic counselor – 7 years
Founder of the Queen Alexandra Charitable Foundation to help children with genetic pathology alixfond.ru
Areas of professional interests: myrobiome, multifactorial pathology, pharmacogenetics, nutrigenetics, reproductive genetics, epigenetics.
Head of
"Prenatal diagnosis"
Kyiv
Yulia Kirillovna
In 2011 she graduated from the Moscow State Medical and Dental University. A.I. Evdokimova with a degree in General Medicine. She studied residency at the Department of Medical Genetics of the same university with a degree in Genetics.
In 2015, she completed an internship in Obstetrics and Gynecology at the Medical Institute for Advanced Training of Physicians of the Federal State Budgetary Educational Institution of Higher Professional Education "MSUPP"
Since 2013, he has been conducting consultations at the State Budgetary Institution "Center for Family Planning and Reproduction" of the Department of Health.
Since 2017, he has been the head of the “Prenatal Diagnostics” direction of the Genomed laboratory
Regularly makes presentations at conferences and seminars. Gives lectures for various specialist doctors in the field of reproduction and prenatal diagnostics
Provides medical and genetic counseling to pregnant women on prenatal diagnostics in order to prevent the birth of children with congenital malformations, as well as families with presumably hereditary or congenital pathologies. Interprets the obtained DNA diagnostic results.
SPECIALISTS
Latypov
Arthur Shamilevich
Latypov Artur Shamilevich is a geneticist doctor of the highest qualification category.
After graduating from the medical faculty of the Kazan State Medical Institute in 1976, he worked for many years, first as a doctor in the office of medical genetics, then as the head of the medical-genetic center of the Republican Hospital of Tatarstan, the chief specialist of the Ministry of Health of the Republic of Tatarstan, and as a teacher in the departments of the Kazan Medical University.
Author of more than 20 scientific papers on problems of reproductive and biochemical genetics, participant in many domestic and international congresses and conferences on problems of medical genetics. He introduced methods of mass screening of pregnant women and newborns for hereditary diseases into the practical work of the center, performed thousands of invasive procedures for suspected hereditary diseases of the fetus. different dates pregnancy.
Since 2012, she has been working at the Department of Medical Genetics with a course in prenatal diagnostics at the Russian Academy of Postgraduate Education.
Area of scientific interests: metabolic diseases in children, prenatal diagnostics.
Reception hours: Wed 12-15, Sat 10-14Doctors are seen by appointment.
Geneticist
Gabelko
Denis Igorevich
In 2009 he graduated from the Faculty of Medicine of KSMU named after. S. V. Kurashova (specialty “General Medicine”).
Internship at the St. Petersburg Medical Academy of Postgraduate Education of the Federal Agency for Healthcare and social development(specialty "Genetics").
Internship in Therapy. Primary retraining in the specialty “Ultrasound diagnostics”. Since 2016, he has been an employee of the department of the Department of Fundamental Principles of Clinical Medicine of the Institute of Fundamental Medicine and Biology.
Area of professional interests: prenatal diagnosis, the use of modern screening and diagnostic methods to identify genetic pathology of the fetus. Determining the risk of recurrence of hereditary diseases in the family.
Participant of scientific and practical conferences on genetics and obstetrics and gynecology.
Work experience 5 years.
Consultation by appointmentDoctors are seen by appointment.
Geneticist
Grishina
Kristina Alexandrovna
She graduated from the Moscow State Medical and Dental University in 2015 with a degree in General Medicine. In the same year, she entered residency in the specialty 08/30/30 “Genetics” at the Federal State Budgetary Institution “Medical Genetic Research Center”.
She was hired at the Laboratory of Molecular Genetics of Complexly Inherited Diseases (headed by Dr. A.V. Karpukhin) in March 2015 as a research assistant. Since September 2015, she has been transferred to the position of research assistant. He is the author and co-author of more than 10 articles and abstracts on clinical genetics, oncogenetics and molecular oncology in Russian and foreign journals. Regular participant in conferences on medical genetics.
Area of scientific and practical interests: medical and genetic counseling of patients with hereditary syndromic and multifactorial pathology.
A consultation with a geneticist allows you to answer the following questions:
Are the child’s symptoms signs of a hereditary disease?
what research is needed to identify the cause
determining an accurate forecast
recommendations for conducting and evaluating the results of prenatal diagnostics
everything you need to know when planning a family
consultation when planning IVF
on-site and online consultations
Geneticist
Gorgisheli
Ketevan Vazhaevna
She is a graduate of the medical and biological faculty of the Russian National Research Medical University named after N.I. Pirogov 2015, defended thesis on the topic “Clinical and morphological correlation of vital indicators of the body’s condition and morphofunctional characteristics of blood mononuclear cells in severe poisoning.” She completed clinical residency in the specialty “Genetics” at the Department of Molecular and Cellular Genetics of the above-mentioned university.
took part in the scientific and practical school "Innovative genetic technologies for doctors: application in clinical practice", the conference of the European Society of Human Genetics (ESHG) and other conferences dedicated to human genetics.
Conducts medical and genetic counseling for families with suspected hereditary or congenital pathologies, including monogenic diseases and chromosomal abnormalities, determines indications for laboratory genetic studies, and interprets the results of DNA diagnostics. Consults pregnant women on prenatal diagnostics to prevent the birth of children with congenital malformations.
Geneticist, obstetrician-gynecologist, candidate of medical sciences
Kudryavtseva
Elena Vladimirovna
Geneticist, obstetrician-gynecologist, candidate of medical sciences.
Specialist in the field of reproductive counseling and hereditary pathology.
Graduated from the Ural State Medical Academy in 2005.
Residency in Obstetrics and Gynecology
Internship in the specialty "Genetics"
Professional retraining in the specialty “Ultrasound diagnostics”
Activities:
- Infertility and miscarriage Vasilisa Yurievna
She is a graduate of the Nizhny Novgorod State Medical Academy, Faculty of Medicine (specialty “General Medicine”). She graduated from clinical residency at FBGNU "MGNC" with a degree in Genetics. In 2014, she completed an internship at the Maternity and Childhood Clinic (IRCCS materno infantile Burlo Garofolo, Trieste, Italy).
Since 2016, he has been working as a consultant physician at Genomed LLC.
Regularly participates in scientific and practical conferences on genetics.
Main activities: Consulting on clinical and laboratory diagnostics genetic diseases and interpretation of results. Management of patients and their families with suspected hereditary pathology. Consulting when planning pregnancy, as well as during pregnancy, on prenatal diagnostics in order to prevent the birth of children with congenital pathologies.
From 2013 to 2014, she worked as a junior researcher at the Laboratory of Molecular Oncology at the Rostov Cancer Research Institute.
In 2013 - advanced training " Current issues clinical genetics", GBOU VPO Growth of the State Medical University of the Ministry of Health of Russia.
In 2014 - advanced training “Application of the real-time PCR method for gene diagnostics of somatic mutations”, Federal Budgetary Institution “Central Research Institute of Epidemiology of Rospotrebnadzor”.
Since 2014 – geneticist at the laboratory of medical genetics at Rostov State Medical University.
In 2015, she successfully confirmed her qualification as a Medical Laboratory Scientist. He is a current member of the Australian Institute of Medical Scientist.
In 2017 - advanced training “Interpretation of the results of genetic studies in patients with hereditary diseases”, NOCHUDPO “ The educational center on continuing medical and pharmaceutical education";
“Current issues of clinical laboratory diagnostics and laboratory genetics”, Rostov State Medical University of the Ministry of Health of Russia; advanced training "BRCA Liverpool Genetic Counseling Course", Liverpool University.
Regularly participates in scientific conferences, is the author and co-author of more than 20 scientific publications in domestic and foreign publications.
Main activity: clinical and laboratory interpretation of DNA diagnostic results, chromosomal microarray analysis, NGS.
Areas of interest: application of the latest genome-wide diagnostic methods in clinical practice, oncogenetics.
Here is a unique book that reveals the causes of missed abortion - the most pressing problem for expectant mothers. After reading it, you will learn about the most common causes of fetal death in the early stages: chromosomal abnormalities, infections, hereditary thrombophilias and many others. The author, a candidate of medical sciences, will tell you how you can prevent the occurrence of these diseases and get a chance to give birth to a baby. In the book, you will also learn about the ancient Chinese secrets of conception and pregnancy, which will help you overcome fear on the path of motherhood.
Fetal chromosomal abnormalities Most common cause
termination of pregnancy is a hereditary pathology in the fetus. More often these are some kind of chromosomal abnormalities, as a rule, incompatible with the life of the fetus and leading to spontaneous miscarriage or the birth of children with developmental defects.
More often, embryos with an incorrect karyotype (set of chromosomes) die in the first weeks of pregnancy. Thus, in the first 6–7 weeks of pregnancy, the majority (60–75%) of dead fetuses have an incorrect karyotype, in 12–17 weeks – a quarter (20–25%), in 17–28 weeks – only 2–7%. We will talk in detail about the types of chromosomal abnormalities (CA) that prevent pregnancy from continuing in this section. Let's start with the basics of genetics.
Secrets of DNA All information about the structure of our body, predisposition to diseases, as well as age-related changes
DNA is located in the cell nucleus as part of chromosomes. Each person has 46 paired chromosomes (Figure 4): the first set (22 chromosomes) we get from one parent, the second from the other. 44 out of 46 chromosomes do not depend on gender, and two determine it: XY in men or XX in women.
Figure 4. Human chromosome set
From a chemical point of view, DNA consists of repeating blocks of nucleotides that form two chains of ribonucleic acid (RNA), twisted together in a spiral (Fig. 5). Therefore, the structure of the DNA molecule is called a “double helix.” DNA is the body's genetic library and is found in every cell. In total, each person has 120 billion miles of DNA.
Figure 5. DNA replication
There are four types of nitrogenous bases found in DNA (adenine, guanine, thymine and cytosine). Their sequence makes it possible to “encode” information about the structure of the entire organism. Chromosomes contain a total of approximately 3 billion base pairs of DNA nucleotides, forming 20,000-25,000 genes.
Cell reproduction occurs through DNA replication (Figure 5). At the same time, it unwinds into two strands of RNA (a). They diverge and form a replication fork (b). Then each RNA becomes a template on which a similar chain is completed (c). As a result, two new double-stranded DNA molecules (d) are formed, identical to the parent molecule.
Protein synthesis occurs in cells in a similar way: DNA unwinds; information is read from it by adding RNA, which leaves the nucleus into ribosomes (cell structures), where it becomes a matrix for protein synthesis; The untwisted DNA rewinds into a helix.
Basics of genetics
Genes are carriers of human hereditary information. Each gene is a section of a DNA molecule that carries information about a specific protein. The complete set of human genes (genotype) is responsible for the functioning of the body, its growth and development. The combination of many genes determines the uniqueness of each person.
Genes are passed on to the child from the parents: one “set” is from the mother, the other from the father. That's why children are so similar to their parents.
If from both parents we inherited the same genes responsible for a trait, for example, blue eye color, then the genotype is considered homozygous for this trait, and the eye color will be blue (Figure 6 a).
If we have inherited different genes (for example, blue eye color from our mother, dark eye color from our father), then the genotype is considered heterozygous (Figure 6 b). In this case, the characteristic that is dominant (predominant) appears, and the eye color will be dark.
Genes are similar in different people, but there are small differences - polymorphisms. Significant changes in genes that lead to disruption of cell function are called mutations (abberrations). In a living cell, genes constantly mutate. The main processes during which failures occur are DNA replication and transcription.
Some changes (polymorphisms or mutations) lead to intrauterine death of the fetus, others become the causes of genetic diseases and appear immediately after birth, while others are a factor that only predisposes to the occurrence of certain diseases.
Figure 6. Homozygous (a) and heterozygous (b) types
Types of Chromosome Disorders
There are two main types of chromosomal disorders (mutations, aberrations):
1. Quantitative changes in the number of chromosomes (aneuploidy): the presence of an extra chromosome (trisomy) or the absence of one of the two paired chromosomes (monosomy). They occur when chromosome segregation is disrupted during cell division, resulting in genetic material being unevenly distributed among daughter cells. Aneuploidy leads to miscarriages or developmental defects.
The most common is trisomy on chromosome 16, which results in early spontaneous miscarriage. Carriers of trisomy on chromosomes 13 (Patau syndrome) and 18 (Edwards syndrome) can survive until birth, but are characterized by significant developmental disorders, and therefore more often die immediately after birth.
The only type of trisomy on autosomal (non-sex) chromosomes, in the presence of which the birth of a viable child is possible, is Down syndrome (trisomy on chromosome 21). I will talk about this pathology in detail in the corresponding chapter.
Chromosomal abnormalities have also been described in which the number of sex chromosomes increases. The most common are: Shereshevsky-Turner syndrome (we will talk about it separately); Klinefelter syndrome (47XXY instead of 46XY), in which the birth of a male baby endowed with some secondary female sexual characteristics is possible, and others.
When a cell has an additional set of chromosomes, polyploidy is formed. For example, when one egg is fertilized by two sperm at once, triploidy occurs (a triple set of chromosomes).
2. There may also be abnormalities in the structure of chromosomes: deletion (loss of a part), inversion (rotation of a chromosome section by 180̊), ring (chromosome forms a ring structure), duplication (repetition of a chromosome section), translocation (transfer of a part of a chromosome to another).
With balanced structural abnormalities of chromosomes, the amount of chromosomal material present is normal, only their configuration is changed. A person with structural chromosome aberrations usually has no manifestations other than possible problems with the reproduction of healthy offspring. Chromosome structure abnormalities can be passed from parent to child.
Down syndrome
The mechanism of occurrence of Down syndrome is a violation of the divergence of chromosomes during the maturation of germ cells (gametes).
During this process, in both men and women, a normal somatic cell, containing a double (diploid) set of chromosomes, divides into two daughter cells with a halved number of chromosomes (Fig. 7). If the number of chromosomes in gametes remained diploid, as in somatic cells, then during fertilization in each generation it would double.
Figure 7. Maturation of germ cells from somatic tissue
When chromosome divergence is disrupted, gametes with the wrong number of them mature. If such a “pathological” germ cell participates in fertilization, then there is a high risk of conceiving a child with a hereditary pathology.
In the presence of an additional 21st chromosome, Down syndrome is formed (Fig. 8). This is one of the forms of genomic pathology in which the karyotype is represented by 47 chromosomes (trisomy 21 chromosomes) instead of 46, that is, from one of the parents (the carrier of the disease), the child received not one 21st chromosome, as expected, but two; the third he received from the other (healthy) parent.
A change in the number of chromosomes is often incompatible with life and leads to the death of the embryo, which is one of the main reasons for miscarriage in the first trimester. However, a fetus with Down syndrome does not always die. Often such children are still born - on average, there is one case in 700 births.
Figure 8. Trisomy 21. Down syndrome
Down syndrome is a severe disorder characterized by dementia, delayed development and the presence of other congenital defects. Currently, thanks to prenatal diagnosis, the birth rate of children suffering from this pathology has decreased to 1 in 1100.
Children with Down syndrome can be born to genetically healthy parents. However, the likelihood of conceiving such a child increases with age. If a woman is over 45 years old, the risk is 1:19. The incidence of this syndrome also increases in a child whose father is over 42 years old.
Shereshevsky–Turner syndrome
One of the reasons for termination of pregnancy is a genetic disease of the fetus such as Shereshevsky-Turner syndrome. This is a chromosomal pathology characterized by the presence of monosomy on the X chromosome (one X chromosome instead of two).
Pregnancy in the presence of such a syndrome in the fetus most often (98%) ends in spontaneous miscarriage in the early stages. If this does not happen, and a girl with Shereshevsky-Turner syndrome is born, she will lag behind in physical development. Typical signs of the syndrome are: short stature, barrel-shaped rib cage, shortened neck. In this case, intelligence most often does not suffer.
Due to a defect or complete absence of one sex X chromosome, the formation of the gonads is disrupted: the ovaries may be completely absent, the uterus may be in its infancy.
Since with this pathology the ovaries usually do not exist, estrogens are not produced. As a result, the level of gonadotropins increases and amenorrhea (absence of menstruation) is noted.
The main type of treatment for patients with Shereshevsky-Turner syndrome is hormonal therapy, which begins at the age of 14–16 years. This leads to feminization of the physique, the development of female secondary sexual characteristics, and reduces the increased activity of the hypothalamic-pituitary system. Therapy is carried out throughout the entire childbearing age of patients. However, women with Shereshevsky–Turner syndrome are infertile due to the absence of ovaries.
How often is pregnancy terminated due to chromosomal abnormalities?
Chromosomal aberrations are the most common cause of miscarriage: from 50 to 95% of cases of spontaneous abortion are caused by chromosomal abnormalities of the fetus. During a frozen pregnancy, the following chromosomal abnormalities are most often detected:
–45–55% – autosomal trisomy,
–20–30% – monosomy,
–15–20% – triploidy.
The parents of a fetus with an increased number of chromosomes are most often healthy, and analysis of their karyotype is not very informative. The risk of recurrence of quantitative chromosomal aberrations (eg, trisomy) in subsequent pregnancies is about 1%, which will require prenatal diagnosis in the first trimester. The married couple should be informed about this in case of fetal death and CA is detected in it.
When structural chromosome aberrations are detected in the fetus, karyotyping of the parents is mandatory, since in families where one of the parents has a chromosome structure disorder (for example, translocation), the risk of spontaneous abortion increases to 25%-50%.
In some cases, with structural aberrations of the fetal chromosomes, pregnancy can progress, and a child will be born with significant developmental defects. The likelihood of a healthy baby being born to parents with structural chromosomal aberrations remains. But in 1-15% of cases it will have genetic abnormalities.
As we have already said, a cytogenetic study of abortion material plays an important role in establishing the cause of spontaneous miscarriage.
Visit to a geneticist
A visit to a geneticist can help determine the reasons for termination of pregnancy.
Question: Tell me what should I do? I couldn’t get pregnant for 4 years, then I succeeded. But at week 6, an ultrasound showed that there was a risk of miscarriage. Then everything was fine, and at 12 weeks bleeding began. They did a second ultrasound and said that the fetus stopped developing at 9 weeks. Please tell me what treatment to get, and will I still be able to get pregnant? Thank you.
Question: I had curettage once, the second time medical abortion, since both pregnancies were frozen. I was tested for hidden infections, the result was negative. There was no birth, I really want a baby. Please tell me what other tests I need to take?
It is the chromosomal pathology of the fetus that leads to its intrauterine death in the early stages of development (the so-called “frozen pregnancy”) and spontaneous miscarriage. Therefore, if you have had miscarriages or a missed pregnancy in the past, you should undergo genetic testing.
Often, expectant mothers are very wary of medical genetic consultation. And in vain! This study allows us to determine in advance the risk of having children with genetic abnormalities.
Such disorders in the fetus can be inherited from one of the parents or caused by adverse external influences: smoking by the expectant mother, drinking alcohol, taking certain medications, previous infections, exposure to radiation during and before conception.
Consultation with a specialist is necessary if:
– future parents or their relatives have any hereditary diseases;
– there is a child in the family with a genetic pathology;
-future parents are relatives;
– the age of the expectant mother is over 35 years, the father – more than 40 years;
–previous pregnancies were missed or ended spontaneous miscarriages;
– future parents were exposed to radiation or worked with harmful chemicals for a long time;
the expectant mother took potent medications during the period of conception and/or in the early stages of pregnancy.
Couples at risk should undergo a medical genetic examination without fail. If desired, any couple planning a child can consult a geneticist.
After pregnancy occurs, special monitoring is established for women at risk. At 10-13 weeks of pregnancy, it is necessary to conduct a prenatal diagnosis of the baby’s health status, which we will talk about later.
First trimester screening
A set of measures aimed at early detection of pathology in the fetus is called prenatal diagnosis. According to the latest order of the Ministry of Health and SR No. 808 dated October 2, 2009, first trimester screening, which is carried out at 11-14 weeks of pregnancy, includes the following studies:
1. Ultrasound of the fetus with assessment:
-thickness of the nuchal space (TN); this is the area between the inner surface of the fetal skin and the outer surface of its soft tissues covering the cervical spine, in which fluid can accumulate; Normally, in the period of 11-14 weeks, TVP is 2-2.8 mm; is a marker of fetal chromosomal disorders, primarily Down syndrome;
–presence and length of the nasal bone (NB); normally at 12-13 weeks it is 3 mm; its absence is suspicious for Down syndrome.
2. Maternal serum markers (“double test”):
– free human chorionic gonadotropin (b-hCG); Normally, at 12 weeks, its level is 13.4-128.5 ng/ml; 13 weeks – 14.2-114.7 ng/ml; 14 weeks – 8.9-79.4 ng/ml; allows you to determine the risk of developing certain trisomies: Down syndrome (21 chromosomes), Edwards syndrome (18) and Patau syndrome (13);
– pregnancy-associated plasma protein A (PAPP-A): normally at 11-12 weeks it is 0.79-4.76 mU/l, at 12-13 weeks – 1.03-6.01 mU/l; 13-14 weeks – 1.47–8.54 mU/l; in Down and Edwards syndrome its level is reduced.
Question: I am 34 years old. At week 12 I passed a “double test”: PAPP-A was normal – 3.07, and hCG was higher than normal (178.0). Ultrasound showed no pathology. Is there any reason to worry? Is it possible to continue pregnancy?
The discrepancy between the first trimester screening results and the norms does not indicate the need for immediate termination of pregnancy, but only signals a possible risk, which, after undergoing the examination, is calculated individually for each patient.
If the presence of a pathology in the fetus is suspected based on screening data, the question of conducting an in-depth (invasive) examination is raised. The most reliable way to make a diagnosis is to study the chromosome set of fetal cells. For this purpose, amniotic fluid is studied (amniocentesis), placental tissue (placentocentesis), chorionic villus (biopsy), and fetal cord blood (cordocentesis).
Comment from the forum : I am 38 years old. I registered for pregnancy only at 11 weeks. At the first screening at 12 weeks, the ultrasound doctor measured the thickness of the nuchal translucency at 2.9 mm, and hCG was also elevated. They sent me to a geneticist, where it turned out that this could be an indicator of Down syndrome. They offered to do an amniocentesis at 18 weeks to accurately determine whether the syndrome exists or not, but I refused. Until recently, I hoped that the doctor was mistaken and did not measure accurately. But at 21 weeks, at the second screening, the same doctor discovered a complex inoperable heart defect and kidney pathology in the child. As they explained to me, these are also signs of Down syndrome. The commission decided to induce artificial birth. It’s a pity that I didn’t trust the doctors earlier. So the first screening is a good thing!
If there is a high risk of chromosomal abnormalities in the fetus, the woman is offered additional invasive examination (amniocentesis, cordocentesis) in order to obtain fetal cells and study their chromosomal composition.
As we have already said, invasive procedures are fraught with a number of complications. Therefore, I quite often encounter the fact that the results of biochemical screening cause a lot of worries and questions in women.
Case study: I see a young patient, Irina, with thrombophilia. One day, after passing the first screening, she wrote me a letter: “Olga, Good evening. I did an ultrasound, everything is fine there. And then the transcript of the biochemical screening arrived, and I’m shocked by it...Can I send you the results?”
The analysis determined a low level of PAPP-A. The computer calculated the probable risk of developing Down syndrome in a child: >1:50.
Irina was very worried, because this was her long-awaited pregnancy after two miscarriages. Is it really Down now? I explained to my patient that PAPP-A decreases not only due to chromosomal pathology of the fetus, but also for other reasons. First of all, a low level of PAPP-A may indicate a threat of miscarriage.
Irina remembered that in her last pregnancy, before the miscarriage, the PAPP-A value was also low. Therefore, we decided to focus on drugs that prevent the occurrence of fetal-placental insufficiency. In addition, I prescribed a repeat course of low molecular weight heparin, a blood thinner.
The girl calmed down. A few weeks later she underwent a second ultrasound screening, according to which the fetus was developing normally. She sent me ideal ultrasound results and wrote that I was also responsible for achieving them)
Well, for those women who, having received the results of the first screening, are worried about the increased risk of developing chromosomal abnormalities in the fetus, I recommend, without waiting for the second screening ultrasound, to undergo a simple examination (unfortunately, it was not possible for Irina).
Non-invasive prenatal test
An alternative to biochemical screening and invasive procedures during pregnancy (chorionic villus sampling, amniocentesis) today is a non-invasive prenatal test (NIPT). It is carried out using a routine venous blood sample from the expectant mother.
5-10% of fetal DNA circulates in the mother's blood. NIPT allows you to extract fetal DNA from a pregnant woman's blood and analyze it using the latest technology.
NIPT is used in many countries around the world: USA, UK, Spain, Germany, France, Italy, Brazil, South Korea, Singapore, Chile, etc. Disadvantages: the test is not performed everywhere and is expensive.
Modern diagnostic technologies make it possible to identify any deviation in the development of the fetus from the earliest stages of pregnancy. The main thing is to undergo all necessary examinations in a timely manner and follow the recommendations of specialists.
Second trimester screening
The tactics of prenatal diagnosis in the second trimester have changed significantly in last years. This is important for expectant mothers with suspected chromosomal pathology in the fetus to know.
Thus, according to an earlier order of the Russian Ministry of Health No. 457 dated December 28, 2000, screening of the second trimester should have included three ultrasound examinations at 22-24 weeks of pregnancy and assessment of biochemical markers of fetal malformations at 16-20 weeks (the so-called “triple test” ): alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG) and estriol (E 3).
The “triple test” was designed to detect fetal malformations, primarily Down syndrome. However, studies conducted over the next 9 years showed that the prenatal diagnostic scheme approved by Order No. 457 does not reduce the frequency of births of infants with congenital defects, for example, Down syndrome. The morbidity of children and their mortality, including intrauterine, remained high, despite the work of antenatal clinics by order of the Ministry of Health of the Russian Federation No. 457. These data are confirmed by comments from the forums:
Comments from the forum:
- Yes, I would generally only do the first screening, if it’s ok, then everything will be great! And no further screenings are needed! Even if they show something “wrong”, is it really possible to have an abortion at this stage? And suddenly he turns out to be absolutely healthy! So you won’t forgive yourself for this for the rest of your life!
-I did the screening twice: the first was normal, the second showed an increased (1:32) risk of Down syndrome! According to the ultrasound, everything was fine, but the doctor recommended amniocentesis, just in case. No pathology was identified. A healthy girl was born!!! So I still don’t understand why I did the second screening and amniocentesis? It’s a pity that there are very few good, thoughtful specialists.
– Personally, I was very disappointed in the second screening. On the first one I was fine, but on the second I was found to have elevated hCG. My doctor told me that this is a fetal pathology. Can you imagine what happened to me!? I shed so many tears! And pregnant women shouldn’t worry! The doctor recommended that I visit a geneticist, but I spat on all the doctors and thought: come what may, because the first screening did not reveal anything! I gave birth to an absolutely healthy baby to everyone’s delight! And now I’m thinking, why did they come up with this stupid second screening? To get on the nerves of pregnant women?
Due to the low information content of the old prenatal diagnostic scheme, it was decided to change it. And in 2009, a new order No. 808n was issued, according to which biochemical screening of the second trimester was EXCLUDED from the prenatal diagnostic scheme!
No more "triple test". It is not necessary to carry out it due to the low information content and the large percentage of subsequent unnecessary invasive interventions.
However, some antenatal clinics in our country they do not have the necessary information about changes in the procedure for examining pregnant women suspected of having chromosomal abnormalities and continue to prescribe a “triple test”. I repeat: there is no need to do this now!
In addition, according to the new order No. 808 of 2009, the time for performing an ultrasound scan in the second trimester has been shifted from a point of 22-24 weeks to more early dates(20-22) so that if abnormalities are detected in the fetus, the woman has the opportunity to terminate the pregnancy before 24 weeks, that is, until the time when the fetus is considered viable. The next ultrasound is recommended to be performed at 32-34 weeks of pregnancy.
Ultrasound signs of Down syndrome in the second trimester are: impaired formation of skeletal bones, expansion of the nuchal translucency, the presence of heart defects, expansion of the renal pelvis, choroid plexus cysts of the brain. If they are identified, a decision may be made to carry out invasive techniques to diagnose Down syndrome and other chromosomal abnormalities.
But this is not all the innovations in the field of prenatal diagnostics carried out in our country. Currently, Russia is approaching world standards in this direction. Don't believe me? I'll tell you about this in detail.
International standard for prenatal diagnosis FMF
In Europe, in recent years, a new industry has emerged - “fetal medicine”, which deals with the health of the baby in the womb. The training of prenatal diagnostic doctors and their certification is carried out within the framework of the Fetal Medicine Foundation (FMF) program, headed by Professor Kypros Nicolaides.
FMF is engaged in research in the field of fetal medicine, diagnosis of anomalies of its development, identification and treatment of various complications of pregnancy, and also provides training and certification of specialists in conducting all types of ultrasound examinations during pregnancy. The purpose of creating the FMF is to organize, implement and control the quality of a standardized examination of pregnant women in the first trimester (11 – 14 weeks) of pregnancy.
According to the international FMF standard, examination within these periods should include:
– qualified ultrasound of the fetus between 11 and 14 weeks;
– determination of biochemical parameters of hCG and PAPP-A.
A standardized FMF examination in the first trimester provides for both theoretical and practical training of doctors performing ultrasound, as well as further testing of the quality of the studies performed. At the same time, a standardized study of maternal blood is carried out with a guarantee High Quality work.
Certification process and educational material FMF courses are brought into line with generally accepted German requirements. Participants who pass the theoretical and practical exams are certified through the FMF-Deutschland society and registered as specialists ultrasound diagnostics and are included on the Internet pages of both FMF-Deutschland and FMF Great Britain.
A certificate for conducting an ultrasound examination at 11-14 weeks of pregnancy can only be issued personally to a certified person. Today, hundreds of domestic ultrasound specialists have received the FMF certificate.
Certified doctors and centers receive software developed by FMF to calculate the risk of fetal chromosomal pathology based on ultrasound and biochemical screening data.
National project "Health"
In Russia at the beginning of this century, the level of prenatal diagnostics lagged significantly behind Europe due to the low level of training of ultrasound doctors.
Each pregnant woman decides for herself the complex ethical question of whether it is worth conducting an examination to identify genetic pathologies of the unborn baby. In any case, it is important to have all the information about modern diagnostic capabilities.
Yulia SHATOKHA, Candidate of Medical Sciences, Head of the Department of Prenatal Ultrasound Diagnostics at the Ultrasound Studio Network of Medical Centers, spoke about what invasive and non-invasive methods of prenatal diagnosis exist today, how informative and safe they are, and in what cases they are used.
Why is prenatal diagnosis needed?
Various methods help predict possible genetic pathologies during pregnancy. First of all, this is an ultrasound examination (screening), with which the doctor can notice abnormalities in the development of the fetus.
The second stage of prenatal screening during pregnancy is biochemical screening (blood test). These tests, also known as “double” and “triple” tests, are taken by every pregnant woman today. It allows you to predict with some degree of accuracy the risk of fetal chromosomal abnormalities.
” It is impossible to make an accurate diagnosis based on such an analysis; this requires chromosomal studies - more complex and expensive.
Chromosomal studies are not mandatory for all pregnant women, but there are certain indications:
future parents are close relatives;
expectant mother over 35 years old;
the presence in the family of children with chromosomal pathology;
miscarriages or missed pregnancies in the past;
diseases potentially dangerous to the fetus suffered during pregnancy;
shortly before conception, one of the parents was exposed to ionizing radiation (X-rays, radiation therapy);
risks identified by ultrasound.
Expert opinion
The statistical probability of having a child with a chromosomal disorder is from 0.4 to 0.7%. But it must be borne in mind that this is a risk in the population as a whole; for individual pregnant women it can be extremely high: the basic risk depends on age, nationality and various social parameters. For example, the risk of chromosomal abnormalities in a healthy pregnant woman increases with age. In addition, there is, and then there is an individual risk, which is determined on the basis of biochemical and ultrasound data.
"Double" and "triple" tests
Biochemical screenings also known as , and in common parlance referred to as "test for Down syndrome" or "test for deformities", carried out at strictly defined periods of pregnancy.
Double test
A double test is done at 10-13 weeks of pregnancy. During this blood test, they look at the following indicators:
free hCG (human chorionic gonadotropin),
PAPPA (plasma protein A, inhibitor A).
The analysis should be done only after an ultrasound scan, the data of which is also used when calculating risks.
The specialist will need the following data from the ultrasound report: date of the ultrasound, coccygeal-parietal size (CPR), biparietal size (BPR), nuchal translucency thickness (TN).
Triple test
The second, a “triple” (or “quadruple”) test, is recommended for pregnant women to take at 16-18 weeks.
This test examines the following indicators:
alpha fetoprotein (AFP);
free estriol;
inhibin A (in case of quadruple test)
Based on the analysis of data from the first and second biochemical screening and ultrasound, doctors calculate the likelihood of such chromosomal abnormalities as:
Down syndrome;
Edwards syndrome;
neural tube defects;
Patau syndrome;
Turner syndrome;
Cornelia de Lange syndrome;
Smith Lemli Opitz syndrome;
triploidy.
Expert opinion
A double or triple test is a biochemical test that determines the concentration in the mother’s blood of certain substances that characterize the condition of the fetus.
How are the risks of chromosomal abnormalities calculated?
The results of biochemical screening, in addition to possible chromosomal pathologies, are influenced by many factors, especially age and weight. To determine statistically reliable results, a database was created in which women were divided into groups by age and body weight and the average values of the “double” and “triple” tests were calculated.
The average result for each hormone (MoM) became the basis for determining the normal limit. So, if the result obtained when divided by MoM is 0.5-2.5 units, then the hormone level is considered normal. If less than 0.5 MoM - low, above 2.5 - high.
What level of risk of chromosomal abnormalities is considered high?
In the final conclusion, the risk for each pathology is indicated as a fraction.
A risk of 1:380 and above is considered high.
Average - 1:1000 and below - this is a normal indicator.
A risk of 1:10,000 or less is considered very low.
This figure means that out of 10 thousand pregnant women with such a level, for example, hCG, only one had a child with Down syndrome.
Expert opinion
A risk of 1:100 and higher is an indication for diagnosing chromosomal pathology of the fetus, but each woman determines the degree of criticality of these results for herself. To some, a probability of 1:1000 may seem critical.
Accuracy of biochemical screening in pregnant women
Many pregnant women are wary and skeptical about biochemical screening. And this is not surprising - this test does not provide any accurate information; on its basis, one can only assume the likelihood of the existence of chromosomal abnormalities.
In addition, the information content of biochemical screening may be reduced if:
pregnancy occurred as a result of IVF;
at the expectant mother's diabetes;
multiple pregnancy;
the expectant mother has excess weight or lack thereof
Expert opinion
As an isolated study, double and triple tests have little prognostic value; when taking into account ultrasound data, the reliability increases to 60-70%, and only when conducting genetic tests the result will be 99% accurate. We are talking only about chromosomal abnormalities. If we are talking about a congenital pathology not associated with chromosome defects (for example, “cleft lip” or birth defects heart and brain), then here reliable result Provide professional ultrasound diagnostics.
Genetic tests for suspected chromosomal abnormalities
Based on the ultrasound findings or if biochemical screening results are unfavorable, the geneticist may suggest to the expectant mother pass the . Depending on the period, this may be a chorionic villus or placenta biopsy, amniocentesis or cordocentesis. Such a study gives highly accurate results, but in 0.5% of cases such an intervention can cause a miscarriage.
Material collection for genetic research is carried out under local anesthesia and ultrasound control. The doctor uses a thin needle to puncture the uterus and carefully remove genetic material. Depending on the stage of pregnancy, this may be particles of chorionic villi or placenta (chorionic or placental biopsy), amniotic fluid (amniocentesis) or blood from the umbilical vein (cordocentesis).
The resulting genetic material is sent for analysis, which will determine or exclude the presence of many chromosomal abnormalities: Down syndrome, Patau syndrome, Edwards syndrome, Turner syndrome (accuracy - 99%) and Klinefelter syndrome (accuracy - 98%).
” Four years ago, an alternative to this method of genetic research appeared - a non-invasive prenatal genetic test. This study does not require obtaining genetic material - it is enough to take blood from the vein of the expectant mother for analysis. The method is based on the analysis of DNA fragments of the fetus, which, during the renewal of its cells, enter the bloodstream of the pregnant woman.
This test can be done starting from the 10th week of pregnancy. It is important to understand that this test is not yet widespread in Russia, very few clinics do it, and not all doctors take its results into account. Therefore, you need to be prepared for the fact that the doctor may strongly recommend an invasive examination in case of high risks based on ultrasound or biochemical screening. Be that as it may, the decision always remains with the future parents.
In our city, non-invasive prenatal genetic tests are performed at the following clinics:
"Avicenna". Panorama test. Non-invasive prenatal genetic diagnosis of aneuploidy 42 t.r. Non-invasive prenatal genetic diagnosis of aneuploidies and microdeletions - 52 rub.
"Almita". Panorama test. Cost from 40 to 54 tr. depending on the completeness of the study.
"Ultrasound studio". Prenetix test. Cost 38 tr.
Expert opinion
Only chromosomal analysis can confirm or exclude chromosomal pathology. Ultrasound and biochemical screening can only calculate the magnitude of the risk. Analysis for pathologies such as Down syndrome, Edwards syndrome and Patau syndrome can be carried out from 10 weeks of pregnancy. This is done by obtaining fetal DNA directly from the structures ovum(direct invasive method). The risk arising from invasive intervention, in the presence of direct indications, is guaranteed to be lower than the risk of chromosomal pathology (approximately 0.2-0.5% according to various authors).
In addition, today any pregnant woman of her own free will can undergo examination for the presence of major genetic diseases in the fetus using a direct non-invasive method. To do this, you just need to donate blood from a vein. The method is absolutely safe for the fetus, but is quite expensive, which limits its widespread use.
Difficult decision
Each woman decides for herself the question of whether diagnosis of genetic diseases is necessary during pregnancy and what to do with the information obtained as a result of research. It is important to understand that doctors do not have the right to put pressure on a pregnant woman in this matter.
Expert opinion
When the pregnancy is up to 12 weeks, a woman can decide for herself whether to terminate the pregnancy if any pathology of the fetus is detected. In more late dates There are good reasons for this: pathological conditions, incompatible with the life of the fetus and diseases that will subsequently lead to severe disability or death of the newborn. In each specific case, this issue is resolved taking into account the duration of pregnancy and the prognosis for the life and health of the fetus and the pregnant woman herself.
There are two reasons why doctors may recommend terminating a pregnancy:
developmental defects in the fetus that are incompatible with life or with the prognosis of profound disability of the child have been identified;
a condition of the mother in which prolongation of pregnancy can cause an unfavorable course of the disease with a threat to the life of the mother.
Prenatal diagnosis - be it biochemical, ultrasound or genetic testing - is not mandatory. Some parents want to have as much as possible complete information, others prefer to limit themselves to a minimum set of surveys, trusting nature. And every choice is worthy of respect.
The human body is a complex multifaceted system that functions at various levels. So that organs and cells can work in correct mode, certain substances must participate in specific biochemical processes. This requires a solid foundation, that is, the correct transmission of the genetic code. It is the underlying hereditary material that controls the development of the embryo.
However, changes sometimes occur in hereditary information that appear in large groups or affect individual genes. Such errors are called gene mutations. In some cases, this problem relates to the structural units of the cell, that is, to entire chromosomes. Accordingly, in this case the error is called a chromosome mutation.
Each human cell normally contains the same number of chromosomes. They are united by the same genes. The complete set is 23 pairs of chromosomes, but in germ cells there are 2 times fewer of them. This is explained by the fact that during fertilization, the fusion of sperm and egg must represent a complete combination of all the necessary genes. Their distribution does not occur randomly, but in a strictly defined order, and such a linear sequence is absolutely the same for all people.
3 years later, the French scientist J. Lejeune discovered that the disorder in humans mental development and resistance to infections are directly related to It was about the extra 21 chromosome. She is one of the smallest, but she has a lot of genes. The extra chromosome was observed in 1 in 1000 newborns. This chromosomal disease is by far the most studied and is called Down syndrome.
In the same 1959, it was studied and proven that the presence of extra X chromosome leads to Klinefelter's disease, in which a person suffers from mental retardation and infertility.
However, despite the fact that chromosomal abnormalities have been observed and studied for quite a long time, even modern medicine is not able to treat genetic diseases. But methods for diagnosing such mutations have been quite modernized.
Causes of an extra chromosome
The anomaly is the only reason for the appearance of 47 chromosomes instead of the required 46. Medical experts have proven that the main reason for the appearance of an extra chromosome is the age of the expectant mother. The older the pregnant woman, the more likely chromosome nondisjunction. For this reason alone, women are recommended to give birth before the age of 35. If pregnancy occurs after this age, you should undergo an examination.
Factors that contribute to the appearance of an extra chromosome include the level of anomaly that has increased globally, the degree of environmental pollution, and much more.
There is an opinion that an extra chromosome occurs if there were similar cases in the family. This is just a myth: studies have shown that parents whose children suffer from a chromosomal disorder have a completely healthy karyotype.
Diagnosis of a child with a chromosomal abnormality
Recognition of a violation of the number of chromosomes, the so-called aneuploidy screening, reveals a deficiency or excess of chromosomes in the embryo. Pregnant women over 35 years of age are advised to obtain a sample amniotic fluid. If a karyotype disorder is detected, the expectant mother will need to terminate the pregnancy, since the born child will suffer from a serious illness throughout her life in the absence of effective treatment methods.
Chromosome disruption is mainly of maternal origin, so it is necessary to analyze not only the cells of the embryo, but also the substances that are formed during the maturation process. This procedure is called the diagnosis of genetic disorders using polar bodies.
Down syndrome
The scientist who first described Mongolism is Daun. An extra chromosome, a gene disease in the presence of which necessarily develops, has been widely studied. In Mongolism, trisomy 21 occurs. That is, a sick person has 47 chromosomes instead of the required 46. The main symptom is developmental delay.
Children who have an extra chromosome experience serious difficulties in assimilating material in school institution, so they need an alternative teaching method. In addition to mental development, there is also a deviation in physical development, namely: slanted eyes, flat face, wide lips, flat tongue, shortened or widened limbs and feet, large accumulation of skin in the neck area. Life expectancy reaches 50 years on average.
Patau syndrome
Trisomy also includes Patau syndrome, in which there are 3 copies of chromosome 13. Distinctive feature is a violation of the activity of the central nervous system or its underdevelopment. Patients have multiple developmental defects, possibly including heart defects. More than 90% of people with Patau syndrome die in the first year of life.
Edwards syndrome
This anomaly, like the previous ones, refers to trisomy. IN in this case We are talking about chromosome 18. characterized by various disorders. Mostly, patients experience bone deformation, an altered shape of the skull, problems with the respiratory system and cardiovascular system. Life expectancy is usually about 3 months, but some babies live up to a year.
Endocrine diseases due to chromosome abnormalities
In addition to the listed chromosomal abnormality syndromes, there are others in which a numerical and structural abnormality is also observed. Such diseases include the following:
- Triploidy is a fairly rare disorder of chromosomes in which their modal number is 69. Pregnancy usually ends early miscarriage, but if the child survives, he lives no more than 5 months, and numerous birth defects are observed.
- Wolf-Hirschhorn syndrome is also one of the rarest chromosomal abnormalities that develops due to deletion of the distal end of the short arm of the chromosome. The critical region for this disorder is 16.3 on chromosome 4p. Characteristic signs- developmental problems, growth delays, seizures and typical features faces
- Prader-Willi syndrome is a very rare disease. With such an abnormality of chromosomes, 7 genes or some parts of them on the 15th paternal chromosome do not function or are completely deleted. Signs: scoliosis, strabismus, delay in physical and intellectual development, fast fatiguability.
How to raise a child with a chromosomal disorder?
Raising a child with congenital chromosomal diseases is not easy. In order to make your life easier, you need to follow some rules. First, you must immediately overcome despair and fear. Secondly, there is no need to waste time looking for the culprit, he simply does not exist. Thirdly, it is important to decide what kind of help the child and family need, and then turn to specialists for medical, psychological and pedagogical help.
In the first year of life, diagnosis is extremely important, since motor function develops during this period. With the help of professionals, the child will quickly acquire motor abilities. It is necessary to objectively examine the baby for vision and hearing pathologies. The child should also be observed by a pediatrician, neuropsychiatrist and endocrinologist.
The carrier of an extra chromosome is usually friendly, which makes his upbringing easier, and he also tries, to the best of his ability, to earn the approval of an adult. The level of development of a special child will depend on how persistently they teach him basic skills. Although sick children lag behind the rest, they require a lot of attention. It is always necessary to encourage a child's independence. Self-service skills should be instilled by your own example, and then the result will not be long in coming.
Children with chromosomal diseases are endowed with special talents that need to be discovered. This could be music lessons or drawing. It is important to develop the baby’s speech, play active games that develop motor skills, read, and also teach him routine and neatness. If you show your child all your tenderness, care, attentiveness and affection, he will respond in kind.
Can it be cured?
To date, it is impossible to cure chromosomal diseases; Each proposed method is experimental, and their clinical effectiveness has not been proven. Systematic medical and educational assistance helps to achieve success in development, socialization and acquisition of skills.
A sick child should be observed by specialists at all times, since medicine has reached the level at which it is able to provide the necessary equipment and different kinds therapy. Teachers will use modern approaches in the education and rehabilitation of the child.
I really want to find those who experienced this and hear how it all ended for them - this is the only thing that will help me not go crazy now.
I am 26, I have a daughter who is almost 4 years old. Second pregnancy - 17 weeks. From 12 weeks my life became hell as soon as I had my first ultrasound. It took place in our perinatal center.
It showed an increase in the collar space - 2.3 mm, dilated pelvis, heart rate - 173 beats/min and bladder - 6 mm. I donated blood and according to their program everything turned out fine. They put the risk of megacystic due to Bladder and offered a referral for an abortion while it was still possible in terms of timing. I refused and was scheduled for a repeat ultrasound in a week.
I couldn’t stand it and went to a paid clinic the day before the next ultrasound - they removed the suspicion of a megacystic, because the urinary tract was 2 mm - the baby peed, but the collar space increased - 2.8 mm. We found a hyperechoic focus in the heart.
The next day, the perinatal ultrasound revealed exactly the same thing. A repeat ultrasound was scheduled in 3 weeks.
Yesterday I had an ultrasound. Heartbeat - 167 beats/min, hyperechoic focus in the heart, slightly dilated pelvis, but above normal, and choroid plexus cysts up to 3.9 mm. A local geneticist insists that all these are minor markers of chromosomal abnormalities of the fetus. It was proposed to make an invasive diagnosis of amniotic fluid for 5 types of abnormalities, but it was also stipulated that most likely this analysis will not show positive results, because according to the signs there is no severe anomaly, but points indicate that there are still violations and they can manifest themselves when the child grows up and is unable, for example, to crawl or walk, he may have problems that will later be discovered by a neurologist or pediatrician. And that this can no longer be cured. Sends me to Moscow to see a geneticist for more advanced diagnostics. And this means time, risks and a lot of money. And with your head you understand that you will have one of 3 results in your hands: 1) the child is healthy and this is good; 2) the child has a serious pathology and it is necessary to terminate the pregnancy so as not to live in hospitals, leaving eldest daughter without a mother; 3) there is a certain set of deviations (to be honest, I don’t even know which ones) with which we will sit and, as now, not know what to do. They gave me 2 weeks to think and act - then everything will become useless.
Do you know what’s drilling into my head the most: I have a daughter with similar abnormalities, as they have just found in the baby - she was born with dilated pelvis and she has a slight arrhythmia. She absolutely healthy child and we simply observe its features among specialists in order to track the dynamics (positive, by the way). But the trouble is that 4 years ago there was no such technology and all these screenings, and by all indicators my daughter was healthy (normal). Therefore, all these coincidences are just speculation.
And I don't even know what to do...
