Феномен коморбидности между моногенными и многофакторными заболеваниями предполагает участие определенного общего числа генов и биологических путей в формировании предрасположенности к заболеваниям – “менделевский код”, который связывает каждое многофакторное заболевание с уникальной совокупностью менделевских локусов. В рамках “омнигенной” модели многофакторных заболеваний гены менделевских болезней могут представлять собой “коровые” гены, которые функционируют в клетках органов-мишеней патологии и участвуют в их патогенезе. Менделевские болезни можно использовать в качестве отправной точки для приоритизации локусов/генов, имеющих отношение к сложным признакам и заболеваниям. Этот подход был применен в данном обзоре на примере приоритизации генов в локусах, связанных с гипертрофической и дилатационной кардиомиопатиями в результате широкогеномных ассоциативных исследований. Функциональная характеристика генов менделевских болезней в генетической структуре подверженности многофакторных заболеваний даст новые знания о “коровых” и “периферических” генах и их сфере компетенции. Анализ “менделевского кода” многофакторных заболеваний важно проводить с использованием мультиомного подхода, что позволит идентифицировать “драйверные” гены и биологические пути, связанные с развитием заболеваний.

Modeling 3D genome organisation has been booming in the last years thanks to the availability of experimental datasets of genomic contacts. However, the field is currently missing the standardisation of methods and metrics to compare predictions and experiments. We present 3DGenBench, a web server available at https://inc-cost.eu/benchmarking/, that allows benchmarking computational models of 3D Genomics. The benchmark is performed using a manually curated dataset of 39 capture Hi-C profiles in wild type and genome-edited mouse cells, and five genome-wide Hi-C profiles in human, mouse, and Drosophila cells. 3DGenBench performs two kinds of analysis, each supplied with a specific scoring module that compares predictions of a computational method to experimental data using several metrics. With 3DGenBench, the user obtains model performance scores, allowing an unbiased comparison with other models. 3DGenBench aims to become a reference web server to test new 3D genomics models and is conceived as an evolving platform where new types of analysis will be implemented in the future.

Уровень спонтанных и радиационно-индуцированных повреждений ДНК в соматических клетках человека варьирует в зависимости от генетических и средовых факторов. Такая вариация может быть ассоциирована с транскрипционными изменениями в клетках, позволяя использовать уровень экспрессии генов в качестве маркеров индивидуальной чувствительности к мутагенному воздействию. Данное исследование было направлено на выявление и характеристику дифференциально экспрессирующихся генов (ДЭГ) в лимфоцитах индивидов с различным уровнем эндогенных фокусов белков репарации ДНК γH2AX и частотой радиационно-индуцированных микроядер (n = 37). Группа с низким уровнем фокусов характеризовалась 0.18 ± 0.02 фокусов γH2AX на клетку и частотой радиационно-индуцированных микроядер 155.78 ± 47.19‰. Группа с высоким уровнем фокусов характеризовалась 0.49 ± 0.07 фокусов γH2AX на клетку и частотой микроядер 78.44 ± 33.21‰. С помощью полнотранскриптомного анализа профиля экспрессии генов было выделено семь ДЭГ (ENST00000424415, CRNDE, ADAMTS1, ENST00000424084, EIF2A, PNPLA5, FRG2C) (FDR < 0.2). Поскольку металлопротеиназа межклеточного матрикса ADAMTS1 может активировать латентную форму TGFβ, а TGFβ вовлечен в радиационно-индуцированный клеточный ответ, в модельной системе на основании клеточной линии HeLa было изучено влияние дифференциальной экспрессии данного гена на транскрипционный профиль. Показано, что 29 из 160 выявленных ДЭГ вовлечены в апоптоз, репарацию ДНК, переход клеточного цикла из стадии G2 в M и сигнальный путь TGFβ. Таким образом, ADAMTS1 может быть рассмотрен в качестве потенциальной мишени для противоопухолевой терапии.

Rafiq syndrome (RAFQS) is a congenital disorder of glycosylation (CDG) that is caused by mutations in the MAN1B1 gene and characterized by impaired protein and lipid glycosylation. RAFQS is characterized by a delay in intellectual and motor development, facial and other dysmorphism, truncal obesity, behavior problems, and hypotonia. We describe a Russian patient with delayed intellectual and motor development, a lack of speech, disorientation in space and time, impaired attention and memory, and episodes of aggression. Screening for lysosomal, amino acid, organic acid, and mitochondrial disorders was normal. The patient was referred for the targeted sequencing of the ""Hereditary Metabolic Disorders"" panel. The genetic testing revealed two heterozygous pathogenic variants in the MAN1B1 gene: the previously reported c.1000C > T (p.Arg334Cys) and the novel c.1065 + 1 G > C. Thus, the patient's clinical picture and genetic analysis confirmed RAFQS in the patient.

Long QT syndrome is a rare ion channel disease of the heart. The main disease manifestations are prolongation QT interval on the ECG and ventricular arrhythmias, which can cause sudden cardiac death at a young age. Diagnosis and treatment of this syndrome is an urgent problem, since in order to prescribe effective therapy, it is necessary to establish the type of syndrome by molecular genetic diagnostics. This review discusses the clinical and genetic various types features of congenital long QT syndrome.

Human induced pluripotent stem cell (iPSC) line, ICGi040-A, was obtained from skin fibroblasts derived from a male patient with mosaic ring small supernumerary marker chromosome 4 (sSMS(4)) and infertility. ICGi040-A cells have karyotype 47,XY,+r(4) in 97% of cells and express a set of pluripotent markers, as well as are able to differentiate in vitro into derivatives of all three embryonic germ layers.

Background: Tardive dyskinesia (TD) is an extrapyramidal side effect of the long-term use of antipsychotics. In the present study, the role of glutamatergic system genes in the pathogenesis of total TD, as well as two phenotypic forms, orofacial TD and limb-truncal TD, was studied.

Methods: A set of 46 SNPs of the glutamatergic system genes (GRIN2A, GRIN2B, GRIK4, GRM3, GRM7, GRM8, SLC1A2, SLC1A3, SLC17A7) was studied in a population of 704 Caucasian patients with schizophrenia. Genotyping was performed using the MassARRAY Analyzer 4 (Agena Bioscience™). Logistic regression analysis was performed to test for the association of TD with the SNPs while adjusting for confounders.

Results: No statistically significant associations between the SNPs and TD were found after adjusting for multiple testing. Since three SNPs of the SLC1A2 gene demonstrated nominally significant associations, we carried out a haplotype analysis for these SNPs. This analysis identified a risk haplotype for TD comprising CAT alleles of the SLC1A2 gene SNPs rs1042113, rs10768121, and rs12361171. Nominally significant associations were identified for SLC1A3 rs2229894 and orofacial TD, as well as for GRIN2A rs7192557 and limb-truncal TD.

Conclusions: Genes encoding for mGlu3, EAAT2, and EAAT1 may be involved in the development of TD in schizophrenia patients.

The study of mitochondrial DNA (mtDNA), particularly the hypervariable segment (HVS1) region, is widely used to reconstruct a population's history, structure, and origin. The origin of the Sakha people living in the north-east of Russia has been discussed for more than 300 years, but up to the present time many aspects of their ethnogenesis remain unclear. In order to clarify the migration routes of the ancient ancestors of the Sakha, we analyzed the mitotypes of 69 unrelated representatives of this ethnic group, whose belonging to the ethnic group was traced to the third generation. In the studied Sakha group, we identified 33 mitotypes, the distribution of which by haplogroups approximately coincides with the data of other studies. The results of a comparative study of Sakha mitotypes according to EMPOP data and literature sources revealed a wide distribution of the identified mtDNA HVS1 haplotypes in many populations of Eurasia. A comparison of the obtained mitotypes with the results of mtDNA sequencing of ancient samples shows that most of the mtDNA lines of modern Sakha have long been located on the territory of Yakutia. West Eurasian and East Asian mtDNA lines were incorporated into the Sakha genome at different times in different ways. The results obtained contribute to a better understanding of the routes of ancient migrations of the ancestors of the Sakha population. © 2022, Lobachevsky State University of Nizhny Novgorod. All rights reserved.

The presence of an extra chromosome in the embryo karyotype often dramatically affects the fate of pregnancy. Trisomy 16 is the most common aneuploidy in first-trimester miscarriages. The present study identified changes in DNA methylation in chorionic villi of miscarriages with trisomy 16. Ninety-seven differentially methylated sites in 91 genes were identified (false discovery rate (FDR) < 0.05 and Δβ > 0.15) using DNA methylation arrays. Most of the differentially methylated genes encoded secreted proteins, signaling peptides, and receptors with disulfide bonds. Subsequent analysis using targeted bisulfite massive parallel sequencing showed hypermethylation of the promoters of specific genes in miscarriages with trisomy 16 but not miscarriages with other aneuploidies. Some of the genes were responsible for the development of the placenta and embryo (GATA3-AS1, TRPV6, SCL13A4, and CALCB) and the formation of the mitotic spindle (ANKRD53). Hypermethylation of GATA3-AS1 was associated with reduced expression of GATA3 protein in chorionic villi of miscarriages with trisomy 16. Aberrant hypermethylation of genes may lead to a decrease in expression, impaired trophoblast differentiation and invasion, mitotic disorders, chromosomal mosaicism and karyotype self-correction via trisomy rescue mechanisms.

Familial hypercholesterolemia (FH) is an autosomal dominant disorder increasing premature cardiovascular diseases risk due to atherosclerosis. Pathogenic mutations in the LDLR gene cause most FH cases. Available treatments are effective not for all LDLR mutations. Testing drugs on FH cell models help develop new efficient treatments. We obtained an iPSC line from peripheral blood mononuclear cells of the patient with heterozygous p.Trp443Arg LDLR mutation. The iPSCs with confirmed patient-specific mutations express pluripotency markers, spontaneously differentiate into three germ layers and demonstrate normal karyotype. Patient-specific iPSCs-derived hepatocyte-like and endothelial cells are promising to develop new targeted therapies for FH.

The development of cellular models for familial hypercholesterolemia (FH) is an important direction for creating new approaches to atherosclerosis treatment. Pathogenic mutations in the LDLR gene are the main FH source. We generated an iPSC line from peripheral blood mononuclear cells of the patient with compound heterozygous c.1246C > T/c.940 + 3_940 + 6del LDLR mutation. The resulting iPSC line with confirmed patient-specific mutations maintains a normal karyotype and a typical undifferentiated state, including morphology, pluripotent gene expression, and in vitro differentiation potential. This iPSC line can be further differentiated toward relevant cells to better understand FH pathogenesis.

Meier-Gorlin syndrome (MGS) is a rare genetic developmental disorder that causes primordial proportional dwarfism, microtia, the absence of or hypoplastic patellae and other skeletal anomalies. Skeletal symptoms overlapping with other syndromes make MGS difficult to diagnose clinically. We describe a 3-year-old boy with short stature, recurrent respiratory infections, short-rib dysplasia, tower head and facial dysmorphisms who was admitted to the Tomsk Genetic Clinic to verify a clinical diagnosis of Jeune syndrome. Clinical exome sequencing revealed two variants (compound heterozygosity) in the ORC6 gene: c.2T>C(p.Met1Thr) and c.449+5G>A. In silico analysis showed the pathogenicity of these two mutations and predicted a decrease in donor splicing site strength for c.449+5G>A. An in vitro minigene assay indicated that variant c.449+5G>A causes complete skipping of exon 4 in the ORC6 gene. The parents requested urgent prenatal testing for MGS for the next pregnancy, but it ended in a miscarriage. Our results may help prevent MGS misdiagnosis in the future. We also performed in silico and functional analyses of ORC6 mutations and developed a restriction fragment length polymorphism and haplotype-based short-tandem-repeat assay for prenatal genetic testing for MGS. These findings should elucidate MGS etiology and improve the quality of genetic counselling for affected families.

Background: Germline alterations in BRCA1, BRCA2, and other genes are responsible for early-onset breast cancer. However, up to 20% of molecular tests report genetic variant of unknown significance (VUS) or novel variants that have never been previously described and their clinical significance are unknown. This study aimed to reclassify variant of unknown significance (VUS) or novel variants by using the ActiveDriveDB database that annotates variants through the lens of sites of post-translational modifications (PTM).

Methods: Our study included thirty-eighth young Buryat BC patients, belonging to the Mongoloid race and anthropologically to the Central Asia. Genomic DNA was extracted from the peripheral blood lymphocytes using the phenol/chloroform method. DNA library were prepared using the Hereditary Cancer SolutionTM kit (Sophia GENETICS, Switzerland) to cover 27 genes, such as ATM, APC, BARD1, BRCA1, BRCA2, BRIP1, CDH1, CHEK2, EPCAM, FAM175A, MLH1, MRE11A, MSH2, MSH6, MUTYH, NBN, PALB2, PIK3CA, PMS2, PMS2CL, PTEN, RAD50, RAD51C, RAD51D, STK11, TP53, and XRCC2. Paired-end sequencing (2 x 150 bp) was conducted using NextSeq 500 system (Illumina, USA).

Results: We re-examined 135 rare variants (41 VUS, 25 conflicting, 64 benign and 5 new variants). We identified 10 out of 135 (7.4%) mutations that affected the sites of post-translational modification in proteins. Of 135 rare mutations, 1 benign variant was reclassified as network-rewiring - motif loss mutation, 3 VUS and 1 new variant were reclassified as distal PTM- mutations, 2 new and 1 benign variant were classified as proximal PTM- mutations and 1 benign and 1 conflicting variant were classified as direct PTM- mutations.

Conclusions: For the first time, 7.4% (10 out of 135) of mutations that affected the sites of post-translational modification in proteins were identified among early-onset breast cancer women of Mongoloid origin.

Skewed X-chromosome inactivation (sXCI) can be a marker of lethal genetic variants on the X chromosome in a woman since sXCI modifies the pathological phenotype. The aim of this study was to search for CNVs in women with miscarriages and sXCI. XCI was assayed using the classical method based on the amplification of highly polymorphic exon 1 of the androgen receptor (AR) gene. The XCI status was analysed in 313 women with pregnancy loss and in 87 spontaneously aborted embryos with 46,XX karyotype, as well as in control groups of 135 women without pregnancy loss and 64 embryos with 46,XX karyotype from induced abortions in women who terminated a normal pregnancy. The frequency of sXCI differed significantly between women with miscarriages and women without pregnancy losses (6.3% and 2.2%, respectively; p = 0.019). To exclude primary causes of sXCI, sequencing of the XIST and XACT genes was performed. The XIST and XACT gene sequencing revealed no known pathogenic variants that could lead to sXCI. Molecular karyotyping was performed using aCGH, followed by verification of X-linked CNVs by RT-PCR and MLPA. Microdeletions at Xp11.23 and Xq24 as well as gains of Xq28 were detected in women with sXCI and pregnancy loss.