In Kazakhstan, there is insufficient data on genetic epilepsy, which has its own clinical and management implications. Thus, this study aimed to use whole genome sequencing to identify and evaluate genetic variants and genetic structure of early onset epilepsy in the Kazakhstani pediatric population. In this study, for the first time in Kazakhstan, whole genome sequencing was carried out among epilepsy diagnosed children. The study involved 20 pediatric patients with early onset epilepsy and no established cause of the disease during the July–December, 2021. The average age at enrolment was 34.5 months, with a mean age at seizure onset of 6 months. Six patients (30%) were male, and 7 were familial cases. We identified pathogenic and likely pathogenic variants in 14 (70%) cases, among them, 6 novel disease gene variants (KCNQ2, CASK, WWOX, MT-CO3, GRIN2D, and SLC12A5). Other genes associated with the disease were SCN1A (x2), SLC2A1, ARX, CACNA1B, PCDH19, KCNT1, and CHRNA2. Identification of the genetic causes in 70% of cases confirms the general structure of the etiology of early onset epilepsy and the necessity of using NGS in diagnostics. Moreover, the study describes new genotype-phenotypic correlations in genetic epilepsy. Despite certain limitations of the study, it can be concluded that the genetic etiology of pediatric epilepsy in Kazakhstan is very broad and requires further research.

Cancer cells can sustain survival independently of exogenous growth factors. To investigate their adaptation to serum deprivation, we analyzed transcriptomic responses in two cancer cell lines. Transcriptome analysis revealed upregulation of mRNAs encoding cholesterol biosynthesis enzymes. This was a critical adaptive response, as a pharmacological inhibition of the pathway with statin triggered a robust apoptotic cell death accompanied by generation of a mitochondrial reactive oxygen species. The mechanistic target of rapamycin complex 1 (mTORC1), a master regulator of cell growth, is known to be engaged in controlling lipid biosynthesis. We detected the high polysomal and preribosomal peaks not only in serum-containing medium but also under serum deprivation, indicating a high rate of protein synthesis and ribosomal biogenesis independent of serum. In addition, the inhibition of mTOR kinase activity substantially reduced polysome abundance, with a more pronounced effect in serum-deprived cancer cells. Notably, the mTOR kinase inhibition also prevented the upregulation of the cholesterol synthesis enzyme that established a direct link between mTOR activity, protein synthesis, and cholesterol biosynthesis. Together, our results show that cancer cells adapt to serum withdrawal by activating the cholesterol synthesis pathway through mTOR-dependent regulation of gene expression and protein synthesis, underscoring a critical mechanism of survival under serum withdrawal.

Introduction. Cardiovascular diseases remain one of the leading causes of mortality worldwide. Endothelial dysfunction, inflammation, and lipid metabolism disorders play a key role in their pathogenesis and may be influenced by genetic factors. Aim: To investigate the association between polymorphisms in the APOE, eNOS, ALOX, and MTHFR genes and the risk of cardiovascular disease. Materials and methods. The study included 40 patients diagnosed with dilated cardiomyopathy and ventricular tachycardia and 52 apparently healthy individuals forming the control group. Genotyping of gene polymorphisms was performed using polymerase chain reaction with restriction fragment analysis and direct sequencing. Results. Among the genetic variants investigated, statistically significant associations with disease susceptibility were identified for the MTHFRrs1801133, MTHFR rs1801131 polymorphisms. In this cohort, the C/C genotype of MTHFR rs1801131 was associated with an increased disease risk. In addition, MTHFR rs1801133 demonstrated a significant association with disease susceptibility under codominant, dominant, and overdominant inheritance models. No statistically significant associations were observed for the remaining polymorphisms (APOE rs429358, APOErs7412, eNOS rs2070744, ALOX15 rs2619112, and rs7612186). Conclusion. The findings of this study suggest that MTHFRrs1801133, MTHFR rs1801131 polymorphisms may contribute to susceptibility to dilated cardiomyopathy with ventricular tachycardia in this cohort, whereas no evidence of association was found for the investigated APOE, eNOS and ALOX15 variants. Given the limited sample size, these findings should be interpreted with caution and require validation in larger, independent studies. Введение. Сердечно-сосудистые заболевания остаются одной из ведущих причин смертности во всём мире. Существенную роль в их патогенезе играют эндотелиальная дисфункция, воспалительные процессы и нарушения липидного обмена, которые могут быть обусловлены генетическими факторами. Цель исследования. Исследовать связь между полиморфизмами генов APOE, eNOS, ALOX и MTHFR и риском сердечно-сосудистых заболеваний. Материалы и методы. В исследование были включены 40 пациентов с дилатационной кардиомиопатией и желудочковой тахикардией и 52 практически здоровых человека контрольной группы. Генотипирование полиморфизмов генов проводилось методом полимеразной цепной реакции с последующим анализом рестрикционных фрагментов и прямым секвенированием. Результаты. Среди исследованных генетических вариантов были выявлены статистически значимые ассоциации с предрасположенностью к заболеваниям для полиморфизмов MTHFR rs1801133 и MTHFR rs1801131. В этой когорте генотип C/C полиморфизма MTHFR rs1801131 был ассоциирован с повышенным риском заболевания. Кроме того, MTHFR rs1801133 продемонстрировал значимую ассоциацию с предрасположенностью к заболеваниям при кодоминантном, доминантном и сверхдоминантном типах наследования. Для остальных полиморфизмов (APOE rs429358, APOE rs7412, eNOS rs2070744, ALOX15 rs2619112 и rs7612186) статистически значимых ассоциаций не наблюдалось. Заключение. Результаты данного исследования позволяют предположить, что полиморфизмы MTHFR rs1801133 и MTHFR rs1801131 могут способствовать предрасположенности к дилатационной кардиомиопатии с желудочковой тахикардией в данной когорте, в то время как для исследованных вариантов APOE, eNOS и ALOX15 никаких доказательств ассоциации обнаружено не было. Учитывая ограниченный размер выборки, эти результаты следует интерпретировать с осторожностью и требуют подтверждения в более крупных независимых исследованиях. Кіріспе. Жүрек-қантамыр аурулары әлем бойынша өлім-жітімнің негізгі себептерінің бірі болып табылады. Олардың патогенезінде эндотелий дисфункциясы, қабыну процестері және липидтік алмасудың бұзылыстары маңызды рөл атқарады. Бұл өзгерістер генетикалық факторлармен байланысты болуы мүмкін. Зерттеу мақсаты. APOE, eNOS, ALOXжәне MTHFR гендерінің полиморфизмдері мен жүрек-қантамыр ауруларының даму қаупі арасындағы байланысты зерттеу және олардың эндотелий дисфункциясы, қабыну және липидтік...

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is characterized by ventricular arrhythmias that occur in response to physical or emotional stress. Structural heart disease is typically absent, and this type of arrhythmia is commonly associated with mutations in the RYR2 gene. CPVT is a leading cause of sudden cardiac death in young individuals. In this study, we describe the generation of induced pluripotent stem cells (iPSCs) both from a healthy donor and a patient diagnosed with CPVT. Materials and methods: A Female individual diagnosed with CPVT ( 33 y.o.) underwent genetic screening through Sanger sequencing, which identified a de novo RYR2 mutation (c.13892A>T; p.D4631V). Peripheral blood mononuclear cells were collected from both the patient and a healthy donor using density gradient centrifugation. These cells were reprogrammed into induced pluripotent stem cells (iPSCs) using the Sendai virus approach. The iPSCs were cultured in Essential 8™ Flex medium under feeder-free conditions. Verification of pluripotency was conducted by various techniques, including immunocytochemistry and G-banding karyotyping. Results: Cells exhibited good morphology, forming colonies with clearly defined edges and a rounded appearance, cells within the colonies were tightly packed. Immunostaining verified the presence of the pluripotency marker TRA-1-60. Karyotype analysis confirmed that all derived cell lines retained stable chromosomal integrity. Conclusion: To serve as a control, iPSCs were successfully generated from a healthy donor. Future perspective includes comparison with patient-derived iPSCs harboring a de novo heterozygous RYR2 mutation (c.13892A>T; p.D4631V). iPSC-based model provides a powerful tool for studying the pathophysiology of CPVT and evaluating potential therapeutic strategies. Acknowledgement: This study was funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan: AP19677442 “Modeling of induced pluripotent stem cells (iPSCs) to improve understanding of the mechanisms underlying electrical heart disorders in Kazakhstani patients”; AP23490249 "Functional assessment of novel genetic mutations causing dilated cardiomyopathy using iPSC derived cardiomyocyte modeling in patients of Kazakhstan"; BR24993023 "Improving the diagnostics and therapy of cardiovascular diseases in Kazakhstan by introducing the correction of metabolism with glucagon-like peptide 1 (GLP-1) drugs"; and Nazarbayev University funding CRP grant 211123CRP1608 “Identification and functional characterization of novel genetic mutations causing dilated cardiomyopathy in patients of Kazakhstan”. Key words: iPSCs, CPVT, cardiac arrhythmia, mutation, personalized medicine

Introduction. Cardiovascular diseases, including atherosclerosis (AS), are the leading cause of morbidity and mortality worldwide, including in Kazakhstan. Lipid metabolism disorders, in particular, hypertriglyceridemia, which is recognized as an independent risk factor, play an important role in the development of AS. Genetic features associated with genes regulating lipid and carbohydrate metabolism (GCKR, SLC22A5, LPL, FLCN, LDLR, APOE) have a significant impact on the formation of dyslipidemia and determine individual metabolic characteristics. Studying the prevalence and effects of these genetic variants in the Kazakh population is particularly important, given its underrepresentation in global genetic research. Aim. The objective of this study was to study the frequency of genetic polymorphisms in genes involved in the regulation of lipid metabolism (GCKR, SLC22A5, LPL, FLCN, LDLR, APOE) in a group of Kazakhstani patients with hypertriglyceridemia and atherosclerosis. Additionally, we analyzed the relationship of the identified genetic variants with the biochemical parameters of the lipid profile. Materials and methods. The study analyzed data from 402 patients with cardiovascular diseases, 144 of whom had hypertriglyceridemia. To identify the genetic determinants of lipid metabolism disorders, full-exome sequencing was performed with a focus analysis of the GCKR, SLC22A5, LPL, and FLCN genes. The identified genetic variants were annotated and classified according to the recommendations of ACMG/AMP. The association of genetic polymorphisms with lipid profile parameters in patients with AS was studied. Results. Sequencing of the entire exome of patients with varying degrees of cardiovascular risk revealed genetic variations affecting triglyceride metabolism. Elevated triglyceride levels were reported in patients of all risk categories, with the highest frequency in very high-risk individuals (82 patients). Analysis of the lipid profile showed that total cholesterol was significantly higher in the high-risk group compared with the low-risk group (228.8±35.2 versus 207.8±30.3 mg/dl; p=0.0467). The level of HDL-C showed an inverse relationship with the level of risk, being the lowest in the very high-risk group (44.6±10.5 versus 50.1±9.9 mg/dl; p=0.0411). Although LDL and non-lipoprotein cholesterol did not show statistically significant differences, there was a tendency to increase them. Triglycerides also tended to increase, but without achieving statistical significance (p>0.05). There was a significant decrease in apolipoprotein A at high risk (p0.05). Conclusions. The study did not reveal a statistically significant association between APOE (p.T388C) and GCKR genotypes with cardiovascular risk. Larger-scale studies are required, taking into account additional factors and an increased sample size. Введение. Сердечно-сосудистые заболевания, в том числе атеросклероз (АС), являются основной причиной заболеваемости и смертности во всем мире, включая Казахстан. Важную роль в развитии АС играют нарушения липидного обмена, в частности, гипертриглицеридемия, которая признана самостоятельным фактором риска. Генетические особенности, связанные с генами, регулирующими метаболизм липидов и углеводов (GCKR, SLC22A5, LPL, FLCN, LDLR, APOE), оказывают значительное влияние на формирование дислипидемий и определяют индивидуальные метаболические характеристики. Изучение распространенности и влияния этих генетических вариантов в казахстанской популяции особенно важно, учитывая ее ограниченное представительство в глобальных генетических исследованиях. Целью данного исследования было изучить частоты встречаемости генетических полиморфизмов в генах, участвующих в регуляции липидного обмена (GCKR, SLC22A5, LPL, FLCN, LDLR, APOE), в группе казахстанских пациентов с гипертриглицеридемией и атеросклерозом. Дополнительно мы анализировали взаимосвязь выявленных генетических вариантов с биохимическими параметрами липидного профиля. Материал и методы. В рамках исследования были проанализированы данные 402 пациентов с сердечно-сосудистыми заболеваниями, из которых 144 имели гипертриглицеридемию. Для выявления генетических детерминант нарушений липидного обмена было выполнено полноэкзомное секвенирование с анализом генов GCKR, SLC22A5, LPL и FLCN. Выявленные генетические варианты были аннотированы и классифицированы в соответствии с рекомендациями ACMG/AMP. Проведена оценка ассоциации генетических полиморфизмов с нарушениями липидного профиля в казахстанской популяции пациентов с сердечно-сосудистыми заболеваниями....

Purpose of the study: To assess the contribution of clonal hematopoiesis of indeterminate potential (CHIP) to the development of atherosclerotic disease in the Kazakhstani cohort, focusing on TET2 and DNMT3A genes, based on next-generation sequencing (NGS) data. Materials and Methods: This study employed an observational cross-sectional design. The cohort comprised 177 women and 225 men, with a mean age of 53.0 ± 9.04 years overall (men: 52.2 ± 9.0 years; women: 53.7 ± 9.0 years). Patients were stratified by degree of cardiovascular risk category (low, high, very high) according to the ESC/EAS (2019) recommendations. In this sample, 74 participants (18.4%) were classified as low-risk, 136 (33.8%) as high-risk, and 192 (47.8%) as very high-risk. For the initial phase of analysis, the two most studied genes, TET2 and DNMT3A, were selected from a total list of 8 priority genes: ASXL1, DNMT3A, JAK2, PPM1D, SF3B1, SFRS2, TET2, and TP53associated with CHIP, based on their high clinical significance and frequency of occurrence in previously published studies. By filtering the data and selecting two priority genes for primary analysis, 41 patients with atherosclerotic disease were selected from the total cohort. Genetic analyses were performed using high-throughput whole-exome sequencing to cover a wide range of genetic variants potentially associated with CHIP and the atherosclerotic process. Variant annotation was performed using international databases (ClinVar, ExAC, 1000 Genomes, etc.), and mutations were interpreted according to the ACMG/AMP classification using the InterVar platform. Statistical data processing included the nonparametric Kruskal-Wallis test, Dunn's test for pairwise comparisons, and Fisher's exact test; a value of p < 0.05 was considered statistically significant. Results: Variants were detected in TET2 (n=35) and DNMT3A (n=6). The median VAF value for TET2 was 50%. The age of patients differed significantly between risk groups (p = 0.026). Most of the variants detected had an ultra-rare frequency according to international databases (<0.1%). One pathogenic variant was identified according to the InterVar classification; the others were predominantly of uncertain significance (VUS). The distribution of variants by risk groups showed no statistically significant differences (p = 0.341). Conclusions: The results demonstrate a potential role of CHIP-associated mutations in the pathogenesis of atherosclerosis. Mutations in TET2 were found to be the most significant. Given the identified genetic features and their association with cardiovascular risk, the findings justify extending the analysis to the full spectrum of CHIP-associated genes to improve the accuracy of risk stratification. Цель исследования: Оценить вклад клонального гемопоэза неопределенного потенциала (КГНП) в развитие атеросклеротического заболевания в казахстанской когорте с упором на гены TET2 и DNMT3A на основе данных секвенирования нового поколения (NGS). Материалы и методы: Проведено обсервационное поперечное исследование. Когорта состояла из 177 женщин и 225 мужчин, средний возраст которых в целом составил 53,0 ± 9,04 года (мужчины: 52,2 ± 9,0 года; женщины: 53,7 ± 9,0 года). Пациенты были распределены по категориям сердечно-сосудистого риска (низкий, высокий, очень высокий) в соответствии с рекомендациями ESC/EAS(2019). В этой выборке 74 участника (18,4%) были отнесены к группе низкого риска, 136 (33,8%) – к группе высокого риска и 192 (47,8%) – к группе очень высокого риска. Для начальной фазы анализа два наиболее изученных гена, TET2 и DNMT3A, были выбраны из общего списка из 8 приоритетных генов: ASXL1, DNMT3A, JAK2, PPM1D, SF3B1, SFRS2, TET2 и TP53, ассоциированных с КГНП, на основании их высокой клинической значимости и частоты встречаемости в ранее изученных исследованиях. опубликованные исследования. Путем фильтрации данных и выбора двух приоритетных генов для первичного анализа из общей когорты был отобран 41 пациент с атеросклеротическим заболеванием. Генетический анализ был проведен с использованием высокопроизводительного секвенирования всего экзома (NGS, whole-exome sequencing), чтобы охватить широкий спектр генетических вариантов, потенциально связанных с КГНП и атеросклеротическим процессом. Аннотирование вариантов проводилось с использованием международных баз данных (ClinVar, ExAC, 1000 геномов и др.), а мутации интерпретировались в соответствии с классификацией ACMG/AMP с использованием платформы InterVar. Статистическая обработка данных включала непараметрический критерий Крускала-Уоллиса, критерий Данна для парных...