The role of maternal HLA-DR and HLA-G loci in determining the risk of sporadic congenital heart defects in the next generation

The paper considers the role of maternal HLA-DR (Human Leukocyte Antigens-DR) and HLA-G (Human Leukocyte Antigen-G) loci in determining the risk of the formation of sporadic congenital heart defects without chromosomal diseases in the next generation. The HLA-G molecule expressed on trophoblast performs a protective function by blocking killer receptors on natural killer cells (NK cells). At the same time, the maternal alleles of HLA-DRB1 restrict the immune response to allogeneic antigens of the paternal embryo, which may affect the severity of inflammation in the mother-embryo system and through this mechanism induce the formation of heart disease.Objective: to study the frequency distribution of the combinations of alleles and genotypes of HLA-G 3’UTR and HLA-DRB1 in women with children with sporadic congenital heart defects without chromosomal diseases. Children characteristics and research methods. There were formed 2 groups: Main Group (103 women with children with sporadic congenital heart defects without chromosomal diseases) and Control Group (103 women with conditionally healthy children). Genomic DNA was isolated by phenol-chloroform extraction. Typing of HLA-G 3’UTR 14-bp insertion/deletion was performed by amplification of polymorphic regions of genes by polymerase chain reaction with further electrophoretic detection in polyacrylamide gel 6.0. The frequency analysis of 14 alleles of the HLA-DRB1 gene was performed by real-time polymerase chain reaction. In the course of this work the authors identified predictor and protective combined genotypes.Conclusion. HLA-DRB1 and HLA-G 3’UTR 14-bp ins/del (rs 1704) make a significant contribution to determining the risk of the formation of sporadic congenital heart defects without chromosomal diseases in the next generation.

Changes in the expression of HLA-DR on lymphocyte subpopulations of spouses having children with sporadic congenital heart defects without chromosomal diseases, under the influence of female’s autoserum

This study is aimed to investigate the effect of female autoserum on the HLA-DR expression in various subpopulations of lymphocytes obtained from spouses with children with sporadic congenital heart defects without chromosomal diseases. 78 married couples with children with congenital heart disease were included in the study group. The control group was formed from 35 married couples with healthy children. The immune response in a mixed culture of lymphocytes of spouses was evaluated by an increased HLA-DR expression in a mixed culture in relation to spontaneous cultures of lymphocytes. Primary staining of female and male lymphocytes by monoclonal antibodies to CD45 conjugated with various fluorescent dyes (PC-5 and PC-7) was performed to assess the immune response of female lymphocytes to male ones and vice versa. The activating effect of female autoserum on all subpopulations of female lymphocytes simultaneously occurred significantly less frequently in the study group compared to the control. The control group was characterized by the domination of the positive effect of female autoserum on HLA-DR expression for all subpopulations of female lymphocyte. For all female lymphocytes having HLA-DR molecule on its membrane, the blocking effect of female autoserum in the study group was significantly more expressed in relation to the control group. Thus, the effect of female autoserum is manifested in relation to the HLA-DR expression on its own lymphocytes, but not on the lymphocytes of the spouse.

CHROMOSOMAL DISEASES IN THE HUMAN PATHOLOGY

Background. Chromosomal diseases are the cause of 45-50 % of multiple birth defects. Basic research on mutations is performed using genomic technologies to identify a correlation between genotype and phenotype in aneuploidies and to understand its pathogenesis. Objective. The aim of the research is to study the etiology, pathogenesis of symptoms and diagnostics for patients with Down, Klinefelter, Turner syndromes and double aneuploidies by 21 and sex chromosomes. Methods. A literature review by the keywords “Down syndrome”, “Klinefelter syndrome”, “Turner syndrome”, “double aneuploidy” for the period of 2000-2020 was carried out. Results. Down, Klinefelter and Turner syndromes are the most common aneuploidy among viable newborns. Frequency of meiotic non-disjunction events causing these aneuploidies increases with the age of a woman. Identified genes are responsible for pathogenesis of symptoms in trisomy 21, Turner and Klinefelter syndromes. Diagnostics of chromosomal diseases includes prenatal screening programs and postnatal testing. Conclusions. Cytogenetic variants of Down syndrome are simple complete trisomy 21, translocation form and mosaicism. Trisomy 21 is associated with advanced maternal age. Phenotypic manifestations of Down syndrome are associated with the locus 21q22. The maternal and parental nondisjunction of X-chromosomes in meiosis causes Klinefelter and Turner syndromes. These chromosomal diseases are variants of intersexualism with intermediate chromosomal sex. Down-Klinefelter and Down-Turner syndromes are double aneuploidies. Patients have a Down syndrome phenotype at birth, and signs of Klinefelter and Turner syndromes occur during puberty. Diagnosis of aneuploidy is based on the cytogenetic investigation (karyotyping), DNA analysis, ultrasonography and biochemical markers of chromosomal pathology.

The Karyotype Analysis of Sex Chromosome Mosaicism in Prenatal Diagnosis and Their Clinical Outcomes

Objective To analyze the karyotype of sex chromosome mosaicism in our prenatal diagnosis of 14034 pregnant women in their second trimester, and report the rate of sex chromosome mosaicism and their clinical outcomes.Methods A retrospective analysis of cytogenetic studies of 14043 cases of pregnant women from the Genetic Counseling Clinic from May 2017 to January 2020 by amniocentesis, were performed. Results A total of 46 cases of sex chromosome mosaicism were found, and the sex chromosome mosaicism rate was 0.328%, mainly including four types of mosaicism: mos45,X/46,XX(12); mos45,X/46,XY (11); mos47XXX(or XXY or XYY)/46XX(or XY)(11); and other types of complex abnormal karyotype mosaic(12). Among the 46 fetuses with sex chromosome mosaicism, the indications of prenatal diagnosis includes the numerical abnormality of sex chromosome by NIPT(23/46)，the high risk of trisomy 21 by serum screening(12/46)，abnomal ultrosound(4/46), the advanced maternal age(age ≥35)(4/46), and the histories of abnormal pregnancy(3/46). According to the results of cytogenetic analysis and genetic counseling, the pregnant women would decide to continue or terminate their pregnancy. Conclusion Prenatal cytogenetic diagnosis by amniocentesis is an accurate and convenient method and helps to avoid the delivery of fetuses with chromosomal diseases and reduce the risk of fetal malformation.

Direct and reverse ontogenetics of chromosomal diseases

Представлен анализ современных тенденций исследований на стыке молекулярной цитогенетики, вспомогательных репродуктивных технологий и клеточного репрограммирования, направленных на моделирование патогенеза хромосомных заболеваний в динамике индивидуального развития. Current trends in molecular cytogenetics, assisted reproductive technologies and cell reprogramming for the revelation of chromosomal diseases pathogenesis are reviewed.

An algorithm for interpreting the clinical significance of chromosomal microduplications in undifferentiated forms of intellectual disorders

Идентификация хромосомных аномалий на субмикроскопическом уровне и установление их роли в этиологии интеллектуальных расстройств являются важной научной и практической задачей. Оценка патогенного значения менее изученного типа вариаций копийности ДНК - хромосомных микродупликаций представляет актуальный предмет для обсуждения. В исследовании предложен алгоритм интерпретации клинической значимости частичных трисомий, который является неотъемлемой составляющей в диагностике и профилактике хромосомных болезней. The identification of chromosomal abnormalities at the submicroscopic level and the establishment of their role in the etiology of intellectual disorders are an important scientific and practical task. Evaluation of the pathogenic value of the less studied type of copy number variation - chromosomal microduplication - is an actual issue. The study proposed an algorithm for interpreting the clinical significance of partial trisomies, which is an integral component in the diagnosis and prevention of chromosomal diseases.

Treatment of Epilepsy Associated with Common Chromosomal Developmental Diseases

Chromosomal diseases are heterogeneous conditions with complex phenotypes, which include also epileptic seizures. Each chromosomal syndrome has a range of specific characteristics regarding the type of seizures, EEG findings and specific response to antiepileptic drugs, significant in the context of the respective genetic etiology. Therefore, it is very important to know these particularities, in order to avoid an exacerbation of seizures or some side effects. In this paper we will present a review of the epileptic seizures and antiepileptic treatment in some of the most common chromosomal syndromes.

Роль материнских полиморфных вариантов гена HLA-G3'UTR 14-bp *ins/del в реализации генетического детерминирования риска формирования спорадических септальных врожденных пороков сердца без хромосомных болезней

Врожденные пороки сердца (ВПС) являются ведущей патологией среди всех пороков и аномалий развития плода. Известно, что тератогенный эффект ксенобиотика будет максимально представлен при нарушенных иммунных взаимодействиях в системе мать-эмбрион . Неоднократно показано, что женский гомозиготный генотип HLA-G 3UTR 14-bp ins/ins ассоциирован с репродуктивными потерями. Цель исследования. Изучить распределение аллелей и генотипов генов биотрансформации ксенобиотиков у женщин, имеющих детей с ВПС, носительниц вариантных генотипов HLA-G 3UTR 14-bp ins/del. Материал и методы. Обследованы 103 женщины, у которых дети при рождении имели врожденный порок сердца без хромосомных заболеваний и родословной историей, а также 103 женщины (контрольная группа), родивших двух здоровых детей и более. Типирование полиморфных сайтов генов HLA-G 3UTR 14-bpins/del, GSTM1 (rs74837985), CYP1A1 (rs1048943) CYP1A2 (rs35694136, rs762551) GSTT1 (rs2266633, rs2266637, rs2234953) GSTP1 (rs6591256, rs1695, rs1871042, rs1793068), GATA 6 (rs10454095) проводили методом RT-PCR. Результаты. Показано, что у женщин основной группы, являющихся носительницами гомозиготного генотипа 14-bp ins/ins HLA-G 3UTR, статистически значимо чаще встречались гетерозиготные генотипы GSTP1 (rs6591256) A/G (р0,01 отношение шансов ОШ5,1, 2,5710,27), GSTP (rs1793068) G/T (р0,01 ОШ5,1, 2,5710,27), CYP1A2 (rs762551) A/C (р0,01 ОШ6,81, 3,3513,73) и гомозиготный минорный генотип GSTP1 (rs1871042) T/T (р0,001 ОШ7,32, 3,6214,76) по сравнению с группой контроля. В основной группе женщин G/G rs74837985 GSTM1 статистически значимо реже (р0,01 ОШ 0,20, 0,06-0,59) встречался у носительниц 14-bp ins/ins HLA-G 3UTR по сравнению с носительницами гетерозиготного генотипа 14-bp ins/del HLA-G 3UTR. Заключение. В ходе исследования установлено, что при одновременном носительстве мутантных аллелей HLA-G и генов системы транформации ксенобиотиков риски рождения детей с дефектом межжелудочковой перегородки выше, чем при носительстве изолированных мутаций.Congenital heart defects (CHD) are the leading pathologies among all congenital malformations and fetal development abnormalities. It is known that the teratogenic effect of xenobiotic will be maximally presented in the case of disturbed immune interactions in the mother-embryo system. It has been repeatedly shown that the female homozygous genotype HLA-G 3UTR 14-bp ins/ins is associated with reproductive losses. The purpose of this study was to study the distribution of alleles and genotypes of xenobiotic biotransformation genes in women with children with CHD, carriers of variant HLA-G 3UTR 14-bp ins/del genotypes. Material and method: It was examined 103 women whose children had a ventricular septal defect (VSD) without chromosomal diseases and a pedigree history at birth, and 103 women (control group) who gave birth to two or more healthy children. The typing of polymorphic sites of the genes HLA-G 3UTR 14-bp ins/del, GSTM1 (rs74837985), CYP1A1 (rs1048943) CYP1A2 (rs35694136, rs762551) GSTT1 (rs2266633, rs2266637, rs2234953) GSTP1 (rs6591256, rs1695, rs1871042, rs1793068), GATA 6 (rs10454095) was performed by the RT-PCR method. Mathematical processing was carried out using the application software STATISTICA 8.0 (StatSoftInc., USA) and SNPstats. Results: It was shown that the heterozygous genotypes GSTP1 (rs6591256) A / G (p0.01, OR5.1 (2.5710.27)), GSTP (rs1793068) G / T (p0.01, OR5.1 (2.5710.27)), CYP1A2 (rs762551) A/C (p0.01, OR6.81 (3.3513.73)) and the homozygous minor genotype GSTP1 (rs1871042) T/T (p0.001, OR7.32 (3.6214.76) ) were statistically significantly more frequent in the main group of women who are carriers of the homozygous genotype 14-bp ins/ins HLA-G 3UTR, in comparison with the control group. In the main group of women G/G rs74837985 GSTM1 statistically significantly less (p0.01, OR0.20 (0.060.59)) was found in carriers of 14-bp ins / ins HLA-G 3UTR, in comparison with carriers of the heterozygous genotype 14-bp ins/del HLA-G 3UTR. Conclusion: It was found that with the simultaneous carrier of the mutant alleles of HLA-G and the genes of the xenobiotics transformation system, the risk of having children with VSD is higher, compared with the carriage of isolated mutations.