Anna Bocharova

Forensic and population genetic characteristics of 62 X chromosome SNPs revealed by multiplex PCR and MALDI-TOF mass spectrometry genotyping in 4 North Eurasian populations.

X chromosome genetic markers are widely used in basic population genetic research as well as in forensic genetics. In this paper we analyze the genetic diversity of 62 X chromosome SNPs in 4 populations using multiplex genotyping based on multi-locus PCR and MALDI-TOF mass spectrometry, and report forensic and population genetic features of the panel of X-linked SNPs (XSNPid). Studied populations represent Siberian (Buryat and Khakas), North Asian (Khanty) and Central Asian (Kazakh) native people. Khanty, Khakas and Kazakh population demonstrate average gene diversity over 0.45. Only East Siberian Buryat population is characterized by lower average heterozygosity (0.436). AMOVA analysis of genetic structure reveals a relatively low but significant level of genetic differentiation in a group of 4 population studied (FST=0.023, p=0.0000). The XSNPid panel provides a very high discriminating power in each population. The combined probability of discrimination in females (PDf) for XSNPid panel ranged between populations from 0.99999999999999999999999982 in Khakas to 0.9999999999999999999999963 in Buryats. The combined discriminating power in males (PDm) varies from 0.999999999999999792 to 0.9999999999999999819. The developed multiplex set of X chromosome SNPs can be a useful tool for population genetic studies and for forensic identity and kinship testing.

Polymorphisms of CYP2C8, CYP2C9 and CYP2C19 and risk of coronary heart disease in Russian population

Epoxyeicosatrienoic acids (EETs) are important vasoactive products of arachidonic acid metabolism with a wide range of biological actions in the cardiovascular system. The present study investigated whether single nucleotide polymorphisms (SNP) of genes coding cytochrome P450 2C subfamily, enzymes involved in biosynthesis of EETs, are associated with the risk of coronary heart disease (CHD). A total of 1255 unrelated Russian subjects comprising 561 patients with angiographically diagnosed CHD and 694 age- and sex-matched healthy subjects were included in the study. DNA samples from all study participants were genotyped for six common SNPs rs7909236, rs1934953 of CYP2C8, rs9332242, rs4918758 and rs61886769 of CYP2C9 and rs4244285 of CYP2C19 using by the Mass-ARRAY 4 system. SNP rs4918758 of CYP2C9 was associated with decreased risk of CHD (codominant model) at a borderline significance with odds ratio adjusted for sex and age 0.61 (95% CI: 0.41-0.92, P=0.038, Q=0.20). SNP rs9332242 of CYP2C9 showed a trend towards association with increased CHD risk in cigarette smokers (P=0.049, Q=0.29). Log-likelihood ratio test (LRT) pointed out epistatic interactions between rs9332242 and rs61886769 of CYP2C9 (codominant model, Pinteraction=0.02), however, this P-value did not survive after correction for multiple tests. Bioinformatic analysis revealed a regulatory potential for a majority of the investigated SNPs. Our preliminary results demonstrate that polymorphisms of genes encoding CYP2C subfamily represent potential genetic markers of CHD susceptibility. Further studies are required to substantiate the contribution of these genes to the disease risk.

Development of Multiplex Genotyping Method of Polymorphic Markers of Genes Associated with Cognitive Abilities

A developed method of multiplex genotyping of polymorphic markers of genes associated with cognitive abilities and neuropsychiatric diseases is based on multilocus PCR and MALDI-TOF mass spectrometry of DNA molecules. The frequencies of 32 single-nucleotide markers localized in 24 genes are analyzed in a sample of elderly people from the Russian population of Tomsk. The data obtained are compared with data for populations from the 1000 Genomes Project.

Analysis of Association of Genetic Markers in the LUZP2 and FBXO40 Genes with the Normal Variability in Cognitive Performance in the Elderly

Cognitive performance is an important endophenotype for various neurodegenerative and neuropsychiatric traits. In the present study two genetic variants in the leucine-zipper protein (LUZP2) and the F-box 40 protein (FBXO40) genes, previously reported to be genome-wide significant for Alzheimers diseases and schizophrenia, were examined for an association with cognitive abilities in normal elderly from the Russian population. Rs1021261 in the LUZP2 and rs3772130 in the FBXO40 were genotyped by multiplex PCR and MALDI-TOF mass spectrometry in a sample of 708 normal elderly subjects tested for cognitive performance using the Montreal Cognitive Assessment (MoCA). Association of genetic variability with the MoCA scores was estimated by parametric and nonparametric analysis of variance and by the frequency comparison between upper and lower quartiles of MoCA distribution. Significantly higher frequency of “TT” genotype of rs1021261 in the LUZP2 gene as well as “A” allele and “AA” genotype of rs3772130 in the FBXO40 gene was found in a subsample of individuals with the MoCA score less than 20 comparing to the fourth quartiles subsample (MoCA > 25). The data of the present study suggests that genetic variability in the LUZP2 and FBXO40 loci associated with neurodegenerative and neuropsychiatric diseases is also contributed to the normal variability in cognitive performance in the elderly.

A Novel Polymorphism in the Promoter of the CYP4A11 Gene Is Associated with Susceptibility to Coronary Artery Disease

Enzymes CYP4A11 and CYP4F2 are involved in biosynthesis of vasoactive 20-hydroxyeicosatetraenoic acid and may contribute to pathogenesis of coronary artery disease (CAD). We investigated whether polymorphisms of the CYP4A11 and CYP4F2 genes are associated with the risk of CAD in Russian population. DNA samples from 1323 unrelated subjects (637 angiographically confirmed CAD patients and 686 age- and sex-matched healthy individuals) were genotyped for polymorphisms rs3890011, rs9332978, and rs9333029 of CYP4A11 and rs3093098 and rs1558139 of CYP4F2 by using the Mass-ARRAY 4 system. SNPs rs3890011 and rs9332978 of CYP4A11 were associated with increased risk of CAD in women: OR = 1.26, 95% CI: 1.02–1.57, P = 0.004, and Q = 0.01 and OR = 1.45, 95% CI: 1.13–1.87, P = 0.004, and Q = 0.01, respectively. Haplotype G-C-A of CYP4A11 was associated with increased risk of CAD (adjusted OR = 1.41, 95% CI: 1.12–1.78, and P = 0.0036). Epistatic interactions were found between rs9332978 of CYP4A11 and rs1558139 of CYP4F2 (P interaction = 0.025). In silico analysis allowed identifying that SNP rs9332978 is located at a binding site for multiple transcription factors; many of them are known to regulate the pathways involved in the pathogenesis of CAD. This is the first study in Europeans that reported association between polymorphism rs9332978 of CYP4A11 and susceptibility to coronary artery disease.

Frequencies of alleles, genotypes and haplotypes of two polymorphisms in the clusterin gene in the Russian elderly population categorized by cognitive performance

This article contains data on the frequencies of alleles, genotypes and haplotypes of the single nucleotide polymorphisms (SNPs) rs2279590 and rs1532278 in the CLU gene in a cohort of normal elderly from the Russian population. The SNPs have been reported to be associated with Alzheimers disease and cognitive functions in genome-wide and candidate genes association studies. Cognitive performance in sample set was estimated by the Montreal Cognitive Assessment (MoCA). The frequencies of alleles, genotypes and haplotypes of two SNPs were calculated in 3 groups: total sample set, sample set with MoCA score less than 21 (the first quartile) and group with MoCA score more than 24 (the fourth quartile).

Genetic Variants in CSMD1 Gene Are Associated with Cognitive Performance in Normal Elderly Population

Recently, genetic markers rs10503253 and rs2616984 in the CUB and Sushi multiple domains-1 (CSMD1) gene have been reported to be associated with schizophrenia and cognitive functions in genome-wide association studies. We examined the associations of the above SNPs with cognitive performance evaluated by the Montreal Cognitive Assessment (MoCA) tool in a cohort of the normal elderly from the Russian population. Significant association of rs2616984 genotypes with the MoCA scores was found using nonparametric analysis. No association of rs10503253 with MoCA scores was observed using both parametric and nonparametric statistics. Significant combined effect of two-locus CSMD1 genotypes on MoCA scores was demonstrated by median test. Allele “A” and genotype “AA” of rs2616984 were significantly associated with the lower MoCA scores in comparison of 1st and 4th quartiles of MoCA total score distribution. The results suggest that genetic variants in CSMD1 gene are likely a part of genetic component of cognitive performance in the elderly.

Overlapping Pattern of Genetic Associations of Alzheimer’s Disease And Schizophrenia Mediated By Cognitive Endophenotypes Genes

Background Replicative analysis of genetic markers, previously identified in genome-wide association studies (GWAS) for neuropsychiatric diseases, in population of various origin may contribute to better understanding of genetic composition of the diseases. Methods In this study 50 SNPs found in GWAS for schizophrenia (SZ), Alzheimer’s diseases (AD) and cognitive endophenotypes were genotyped in patients and control samples from Russian and Kazakh populations. Genotyping was performed by TaqMan assays and MALDI-TOF mass-spectrometry. Results Eight polymorphic markers (SNPs in regions of genes for APOЕ, APOJ, CSMD1, CCDC60, SNX29, PICALM, NOTCH4 and NRIP1) were associated with AD in Russian population. Associations of 10 genetic markers with SZ in Russian populations (markers in regions of genes for NRGN, KCNB2, NRIP1, CCDC60, LSM1, LOC100129100 / LOC100509857, CSMD1, СPVL, POM121L2 and NDE1P1 / PRMT6) and 8 genetic markers in Kazakh population (VRK2, KCNB2, СPVL, BRD1, PVRL2, ARHGAP1, CD33 и GPR89P / TRV-AAC1-5) were replicated. Multidimensional reduction methods revealed epistatic interaction of several genetic loci in formation of susceptibility to SZ in populations of various ethnic origin. Discussion Overlapping fields of genetic associations for AD and SZ, demonstrating some similarity in inherited background for both diseases, were found. This interaction may be implemented through common unknown levels in pathogenesis of AD and SZ, mediated by cognitive endophenotypes. Bioinformatic analysis of biological functions of associated genes revealed that among primary biological processes enriched by genes under study are the processes of lipid metabolism, cellular interactions, various regulatory and transport processes in neural cells, processes of immune response regulation. Substantial part of investigated genes forms an interacting network, which consisted of distinct clusters corresponding to major biological processes, were genes under study are involved, and to basic molecular functions of their products. Data obtained in the project, extend the understanding of genetic component in neuro-psychiatric diseases, as well as the biological processes and functions, implemented in the manifestation of genetic susceptibility to AD and SZ.

Replicative Analysis Of 30 Snps In Russian Patients With Alzheimer’s Disease

Background Alzheimer’s disease is a highly heritable genetically heterogeneous disorder with 60%–80% of risk attributed to genetic factors. Two forms of the disease are known as Early-onset familial Alzheimers disease and Late-onset sporadic Alzheimers disease. Although scientists know how brain cells of persons with Alzheimers disease are affected, and additionally understand some of the genetic explanations of the disease, the precise cause of this disease is still unclear. There are over 90 Genome-Wide Association Studies for Alzheimers disease. However, only a few associations were replicated in independent data. The aim of this study was to analyze associations of 30 SNPs reported in GWAS with Alzheimer’s disease in Russian population of Siberian region. Methods 108 patients with AD and 285 healthy controls, matched to the patients by age, gender, and ethnicity were included in this study. 30 SNPs were genotyped by MALDI-TOF mass-spectrometry using MassARRAY Analyzer 4 (Sequenom). Allele-specific ORs and associated p-values were calculated. Results We found three significant associations of SNPs with AD in Russian patients of Siberian region: rs17594526 at TCF4 gene (OR = 1.77, p=0.003), rs11064768 at CCDC60 gene (OR = 2.15, p= 0.02) and rs12922317 at SNX29 gene (OR = 1.47, p= 0.02). These genetic markers were previously reported in GWAS associated with schizophrenia. Discussion Only the TCF4 gene has known functional importance for cognitive dysfunctions of schizophrenia and Alzheimers disease. As a transcription factor, the TCF4 gene regulates the expression of other genes involved in cell differentiation, survival, and neurodevelopment. Genetic markers of CCDC60 and SNX29 are associated with Alzheimer’s disease but their role in pathogenesis of the disease is not clear. This work was supported by the Russian Science Foundation (project # 16-14-00020).

The contribution of CYP2C gene subfamily involved in epoxygenase pathway of arachidonic acids metabolism to hypertension susceptibility in Russian population

ABSTRACT Numerous studies demonstrated an importance of cytochrome P-450 epoxygenase pathway of arachidonic acids metabolism for the pathogenesis of essential hypertension (EH). The present study was designed to investigate whether common single-nucleotide polymorphisms (SNP) of CYP2C gene subfamily such as CYP2C8 (rs7909236 and rs1934953), CYP2C9 (rs9332242), and CYP2C19 (rs4244285) are associated with susceptibility to EH in Russian population. A total of 816 unrelated Russian individuals comprising 425 EH patients and 391 normotensive controls were included into the study. Genotyping of SNPs was performed using the MassARRAY 4 system. SNP rs7909236 of CYP2C8 was significantly associated with increased risk of EH (OR adjusted for sex and age was 2.99 95% CI 1.39-6.44, P = 0.005). SNPs rs1934953 CYP2C8 and rs4244285 of CYP2C19 showed association with EH risk but at a borderline statistical significance (P ≤ 0.04). Combination of genotypes CYP2C8 rs7909236 TT and CYP2C19 rs4244285 GG was associated with increased EH risk (OR 3.34 95%CI 1.48-7.51, P = 0.004). Genotype–phenotype correlation analysis showed that the levels of CYP2C8 mRNA were significantly correlated with SNP rs7909236 (P = 0.01). in silico functional prediction analysis revealed the functionality of majority of investigated SNPs. Thus, genes of CYP2C subfamily are important genetic determinants of susceptibility to essential hypertension in Russians.