[Association study of genetic markers of schizophrenia and its cognitive endophenotypes].

A replicative analysis of associations of 15 SNPs located in the regions of 11 genes (TCF4, VRK2, NOTCH4, ZNF804A, AGBL1, RELN, ZFP64P1, KCNB2, CSMD1, CPVL, NRIP1) and three intergenic regions (SLCO6A1/LINCOO491, LOC105376248/LOC105376249, SPA17/NRGN) with schizophrenia was conducted in the Russian population of the Siberian region. These SNPs were previously identified in genome-wide association studies (GWAS) of schizophrenia and cognitive abnormalities. The present study confirmed associations of KCNB2 rs2247572, CSMD1 rs2616984, and intergenic rs12807809 located in SPA17/NRGN with schizophrenia. It was established that the frequency of the CSMD1 rs2616984 G/G genotype was higher in patients compared to the control group (OR = 1.73; CI: 1.14­2.62; р = 0.0337). The frequencies of the KCNB2 rs2247572 TT genotype (OR = 0.41; CI: 0.20­0.87; р = 0.0485) and intergenic rs12807809 CT genotype located in SPA17/NRGN (OR = 0.70; CI: 0.53­0.94; р = 0.0464) were significantly decreased in patients compared to the control group.

[Haplotype Analysis of Oculopharyngeal Muscular Dystrophy (OPMD) Locus in Yakutia].

Oculopharyngeal muscular dystrophy (OPMD) is a hereditary neuromuscular disease with autosomal dominant and rarely with autosomal recessive inheritance types. This study included 50 patients with a clinical diagnosis of OPMD, 23 asymptomatic carriers of the mutation from 45 unrelated families, and 56 healthy relatives, as well as population samples of four ethnic groups of Yakutia: Yakuts, Evens, Evenks, Yukaghirs. It was found that the cause of OPMD development in all investigated families is the same increase in.GCN repeats to 14 copies in the PABPN1 gene. The molecular structure ofthe (GCN)14 mutant allele is (GCG)10(GCA)3GCG. The genetic variability of ten SNPs at the OPMD locus was studied in patient families and population samples. The haplotypes of OPMD were determined by a segregation analysis technique using the EM algorithm in the groups of patients, mutation carriers, and population samples. Only one haplotype of four SNPs (ATCG) linked with the (GCN)14 mutant allele was found in Yakuts and Russian patients and OPMD mutation carriers. Probably, this indicates the accumulation of mutations as a result of the founder effect.

[Analysis of Eight Polymorphic Alu Elements in the Teleuts Population].

Allele frequencies and genetic diversity in the population of Teleuts were assessed by the Alu repeat polymorphism at eight autosomal loci (ACE, APOA1, PLAT, F13, PV92, A25, CD4, Dl). For comparison, the study included previously obtained data on the Alu polymorphism in 19 indigenous populations of Siberia. On the dendrogram of genetic distances, the Teleut population is located in the cluster of Siberian ethnic groups, which are similar in origin, geography, and cultural traditions.

[Replicative study of susceptibility to childhood-onset schizophrenia in Kazakhs].

This paper reports the results of replicative analysis of associations of 15 SNPs in a region of 14 genes previously identified in genome-wide association studies (GWAS) with early-onset schizophrenia in Kazakhs. An association of early-onset schizophrenia with genetic markers in three genes (VRK2, KCNB2, and CPVL) was found. An association of rs2312147 in the VRK2 gene with schizophrenia was also previously reported in the Chinese population, so this marker may be considered as possibly race-specific. Two groups consisting of four and six genes demonstrating intergenic epistatic interactions were revealed by multifactor dimensionality reduction methods. The gene ontologies of 14 studied genes were reduced to variants of one molecular function (peptidase activity) and one biological process (positive regulation of biosynthesis processes). Bioinformatic analysis of the protein-protein interactions of products of the genes under study demonstrates that the products of six out of 14 genes may be involved in a single interrelated network, the major connecting link of which is represented by their ubiquitination by the UBC protein.

[Replicative association analysis of genetic markers of cognitive traits with Alzheimer's disease in a Russian population].

Replicative association analysis of Alzheimer's disease (AD) with 15 genetic markers associated with cognitive traits in genome-wide association studies was performed. In a Russian populations associations of rs2616984 in CSMD1 gene with AD (OR = 1.50, 95% CI = 1.07-2.09, p-value = 0.018) and putative associations with the disease of rs3131296 in NOTCH4 gene (OR = 1.53, 95% CI = 0.98-2.39, p-value = 0.06) and rs2229741 of NRIP1 gene (OR = 1.35, CI = 0.99-1.85, p-value = 0.061) were revealed. Combinations of epistatic interacting genes (CSMD1 and NRIP1; NOTCH4, CSMD1 and NRIP1; TLR4, CSMD1 and NRIP1) were found, as well as their genotypes combinations significantly associated with AD and characterized by highest predictive values. Probable molecular mechanisms implicated in the relation of genes under study to AD pathogenesis are discussed. Bioinformatic analysis of biological processes, molecular functions and protein-protein interactions of BA genes demonstrated that genes under study may play modulating and modifying role by participation in various regulatory and signal pathways involved in a disease development.

[Biochip for determination of genetic markers of sporadic Alzheimer's disease in the Russian Slavic population].

A biological microchip (biochip) for the genetic predis- position to sporadic form of Alzheimer's disease studying has been developed. The biochip allows determina- tion of ten genetic polymorphisms within APOE, TOMM40, APOJ, EXOC3L2, GAB2, A2M, CR1, BIN1 and PICALM genes. The genotyping assay includes the amplification of loci of interest and further allele-specific hybridization of the fluorescent labeled amplicons with oligonucleotides immobilized on a biochip. Based on the results of genotyping of 166 patients and 128 controls APOE epsilon4 allele was found to be significantly associated with Alzheimer's disease susceptibility (OR = 2.275, 95% CI = 1.045-4.954,p = 0.034). Additionally, protective effects for the APOE epsilon2 allele and CLUT-allele (rs11136000) were observed (OR = 0.215, 95% CI = 0.090-0.516, p = 0.001 and OR = 0.679, 95% CI = 0.47-0.99, p = 0.042, respectively). Gene-gene interaction revealed two genotype combinations associated with Alzheimer's disease: APOE E3/E4 GAB2 G/G (OR = 2.49; CI = 1.43-4.32, p = 0.001) and APOE epsilon4 GAB2 G/G (OR = 3.55, CI = 1.23-10.24,p = 0.015). Based on the results of the combined multivariate analysis the algorithm for identifying of individuals at increased risk of Alzheimer's disease was developed.

Relationship of the gene pool of the Khants with the peoples of Western Siberia, Cis-Urals and the Altai-Sayan Region according to the data on the polymorphism of autosomic locus and the Y-chromosome.

Khanty are indigenous Siberian people living on the territory of Western Siberia, mainly on the territory of the Khanty-Mansiysk and Yamalo-Nenets Autonomous Okrugs. The present study is aimed at a comprehensive analysis of the structure of the Khanty gene pool and their comparison with other populations of the indigenous population of Southern and Western Siberia. To address the issues of genetic proximity of the Khanty with other indigenous peoples, we performed genotyping of a wide genomic set of autosomal markers using high-density biochips, as well as an expanded set of SNP and STR markers of the Y-chromosome in various ethnic groups: Khakas, Tuvans, Southern Altaians, Siberian Tatars, Chulyms (Turkic language family) and Kets (Yeniseian language family). The structure of the gene pool of the Khanty and other West Siberian and South Siberian populations was studied using a genome-wide panel of autosomal single nucleotide polymorphic markers and Y-chromosome markers. The results of the analysis of autosomal SNPs frequencies by various methods, the similarities in the composition of the Y-chromosome haplogroups and YSTR haplotypes indicate that the Khanty gene pool is quite specific. When analyzing autosomal SNPs, the Ugrian genetic component completely dominates in both samples (up to 99-100 %). The samples of the Khanty showed the maximum match in IBD blocks with each other, with a sample of the Kets, Chulyms, Tuvans, Tomsk Tatars, Khakas, Kachins, and Southern Altaians. The degree of coincidence of IBD blocks between the Khanty, Kets, and Tomsk Tatars is consistent with the results of the distribution of allele frequencies and common genetic components in these populations. According to the composition of the Y-chromosome haplogroups, the two samples of the Khanty differ significantly from each other. A detailed phylogenetic analysis of various Y-chromosome haplogroups made it possible to describe and clarify the differences in the phylogeny and structure of individual ethnospecific sublines, to determine their relationship, traces of population expansion in the Khanty gene pool. Variants of different haplogroups of the Y-chromosome in the Khanty, Khakas and Tuvans go back to their common ancestral lines. The results of a comparative analysis of male samples indicate a close genetic relationship between the Khanty and Nenets, Komi, Udmurts and Kets. The specificity of haplotypes, the discovery of various terminal SNPs confirms that the Khanty did not come into contact with other ethnic groups for a long time, except for the Nenets, which included many Khanty clans.

[A rare variant in the sortilin-related receptor 1 gene is associated with declined cognitive functions in the elderly]. / Redkii variant v gene sortilinpodobnogo retseptora 1: sviaz' s pokazateliami kognitivnykh funktsii u pozhilykh.

AIM: To estimate the association of rs11218343 in the sortilin-related receptor 1 (SORL1) gene with cognitive performance in the elderly and with Alzheimer's disease (AD) in the Russian population. MATERIAL AND METHODS: A sample included 586 elderly people (mean age 70.9±5.7 years) without AD diagnosis and 100 patients with late-onset AD (mean age 72.1±7.8 years) from the Tomsk population. SORL1 rs11218343 was genotyped using PCR and MALDI-TOF mass spectrometry. Cognitive performance in the sample of elderly without AD was assessed by Montreal Cognitive Assessment (MoCA) test. RESULTS: Allele frequencies of the SORL1 polymorphism were not significantly different between the elderly without AD and AD patients. However mean MoCA score in the carriers of the rare allele (19.00±6.61) was significantly lower than in homozygotes for the common variant (22.25±3.89) (F=4.97; p=0.026). CONCLUSION: The rare variant in SORL1 gene previously associated with AD in genome-wide association studies and meta-analyses was associated with lower total МоСА scores in the random sample of elderly people that suggests declined cognitive functions in the carriers of this variant in elderly.

[Polymorphism of human MDR1 gene in the Siberian and central Asian populations].

The multidrug resistance gene (MDR1, ABCB1) encodes transmembrane P-glycoprotein an ATP-dependent transporter, which is involved in elimination of drugs, xenobiotics, peptides from a cell. It is expressed in such organs as a brain, kidneys, a liver, a gastroenteric tract. It is supposed, that this protein may take part in formation of individual resistance to action of adverse factors of an environment, such as toxic substances, xenobiotics and infectious diseases. A number of polymorphisms in MDR1 gene is associated with a expression level and functioning of the gene, as well as with the ability to eliminate drugs and with the resistance to various neurodegeneration and gastroenteric tract diseases. In this study the frequencies of five single nucleotide polymorphisms (SNPs) (3435C/T, 2677G/T/A, 1236C/T, +139C/T and -1G/A), located in MDR1 gene, frequencies of haplotypes, the genetic differentiation and linkage disequilibrium pattern in populations of Russians, Tuvinians, northern and southern Kirghizes are described. Significant genetic differences were found between populations of Russians and northern Kirghizes, and also between Tuvinians and northern Kirghizes. The linkage disequilibrium pattern is characterized by high population specificity.

[Association analysis of gene polymorphism in alcohol metabolizing enzymes with risk for coronary atherosclerosis].

The allele and genotype distribution of two alcohol dehydrogenase genes ADH1B (exon 3 polymorphism A/G (47His)), ADH7 (intron 5 polymorphism G/C) and cytochrome P450 2E1 gene (CYP2E1; 5'-flanking region G/C and intron 6 T/A polymorphisms) were examined in Russian (Tomsk, n = 125) healthy population and in coronary atherosclerosis patients (CA, n = 92). The genotype frequencies followed the Hardy-Weinberg equilibrium and the alleles were in linkage equilibrium or gametic equilibrium in the control sample. Only two CYP2E1 gene polymorphisms were in linkage disequilibrium. The frequencies of the derived alleles at ADH1B (*G (+MslI) allele), CYP2E1 (**C2 (+PstI) allele) and CYP2E1 (*C (-Dra I)2 allele) were 8.48 +/- 1.86%; 1.20 +/- 0.69% and 10.00 +/- 1.90%, respectively. The 2ADH7 gene polymorphism showed a high level of heterozygosity; the frequency of the ADH7*C (-Sty I) allele was 44.58 +/- 3.21%. A significantly higher frequency of CYP2E1 (*C2 (+Pst I)) allele has been revealed in the CA group (P = 0.043; OR = 4.23; 95% CI 1.03-20.01). The tendency to significant effect of A1A2 genotype in ADH1B Msl 1 polymorphism was observed for systolic blood pressure in the control group (P = 0.068). The statistically significant two-way interaction effects of ADH7 StyI and CYP2E1 DraI on diastolic blood pressure (P = 0.029) and on the serum high density lipoprotein level (P = 0,042) were also revealed. Association of A1A2 genotype in ADHIB Msl I polymorphism with reduced amount in a serum of a very low density lipoprotein level (P = 0.045) have also been shown. This may result from multifunctional activity of alcohol metabolizing enzymes and their involvement in many metabolic and free radical reactions in the body.

[Alcohol dehydrogenases ADH1B and ADH7 gene polymorphism in Russian population from the Siberian region]. / Polimorfizm genov alkogol'degedrogenaz ADH1B i ADH7 v russkikh populiatsiiakh sibirskogo regiona.

The Allele and genotype didtributions of the two alcohol dehydrogenase genes ADH1B (polymorphism A/G in exon 3, detected with restrictase MslI) and ADH7 (polymorphism G/C in intron 5, detected with restrictase StyI) was studied in three Russian populations from the Siberian region. The absence of interpopulation and intersexual differences in the allele frequency was determined. The allele ADH1B*G (+MslI, A2) was found in low frequency (3.6-7.5%), the mutant allele ADH7 (-StyI, B2) frequency in total population (n = 339) was 46.02%. The genotype distributions of the ADH1B and ADH7 in these populations were agreed with the Hardy-Weinberg equilibrium and linkage equilibrium. Increased frequency of ADH7 B2 allele was revealed in elder group (after 40 years) in the total sample and in the Tomsk city inhabitants (n = 113) on 11% (P = 0.001) and 9% (P = 0.017) accordingly. ADH7 and ADH1B genes polymorpisms did not show association with antioxidant activity, which was determined from the blood plasma ability to reduce the yield of products interacting with thiobarbituric acid in the lecitin-Fe2+ ions model system. The statistically significant decrease of serum very low density lipoproteins (LPVLD) level (on 9.95%, P = 0.045) and close to statistically significant decrease systolic pressure (on 6.80%, P = 0.068) and serum triglycerides level (on 6.16 of %, P = 0.058) were revealed among the A2 allele ADH1B gene carriers in Tomsk population.

[Restriction polymorphism of the APOB locus in residents of the city of Tomsk]. / Restriktsionnyi polimorfizm lokusa APOB u naseleniia g. Tomska.

Restriction fragment length polymorphism (RFLP) of the apolipoprotein B locus was investigated in the population of Tomsk. The frequencies of alleles and haplotypes of polymorphic restriction sites XbaI, MspI, and EcoRI were determined. The parameters of linkage disequilibrium and polymorphism information content (PIC) were estimated. Comparative data on various regions of the world are shown.

[Correlation between polymorphic variants of the genes for transferrin and angiotensin-converting enzyme and antioxidant activity of blood plasma]. / Vzaimosviaz' polimorfnykh variantov genov transferrina i angiotenzin-prevrashchaiushchego fermenta s antioksidantnoi aktivnost'iu plazmy krovi.

In 75 male and 46 female subjects of an urban population (93% Russians) and in 38 males and 40 females of a rural population (87% Russians), the antioxidant activity (AOA) of blood plasma was determined from the plasma ability to reduce the yield of products interacting with thiobarbituric acid in the model lecithin-Fe2+ ion system. In the urban population, the loci TF (AvaI in exon5) and ACE (I/D polymorphism of the Alu repeat in intron16) were studied in 130 and 141 subjects, respectively. Of them, 102 and 111 subjects, respectively, were examined for AOA. In the rural population, the corresponding sample sizes were 75 and 76 (73 and 74 subjects were examined for AOA). The polymorphic loci of the urban and rural populations did not differ in the allele frequencies. In both populations Hardy--Weinberg and gametic equilibria were observed. The contributions of the TF and ACE genes to AOA variation in the combined sample from the urban and rural populations were 0.6 and 0.5%, respectively.

Characteristics of Populations of the Russian Federation over the Panel of Fifteen Loci Used for DNA Identification and in Forensic Medical Examination.

Seventeen population groups within the Russian Federation were characterized for the first time using a panel of 15 genetic markers that are used for DNA identification and in forensic medical examinations. The degree of polymorphism and population diversity of microsatellite loci within the Power Plex system (Promega) in Russian populations; the distribution of alleles and genotypes within the populations of six cities and 11 ethnic groups of the Russian Federation; the levels of intra- and interpopulation genetic differentiation of population; genetic relations between populations; and the identification and forensic medical characteristics of the system of markers under study were determined. Significant differences were revealed between the Russian populations and the U.S. reference base that was used recently in the forensic medical examination of the RF. A database of the allelic frequencies of 15 microsatellite loci that are used for DNA identification and forensic medical examination was created; the database has the potential of becoming the reference for performing forensic medical examinations in Russia. The spatial organization of genetic diversity over the panel of the STR markers that are used for DNA identification was revealed. It represents the general regularities of geographical clusterization of human populations over various types of genetic markers. The necessity to take into account a population's genetic structure during forensic medical examinations and DNA identification of criminal suspects was substantiated.

Plasma antioxidant activity and chromosome aberrations in humans exposed to long-term low-dose gamma-irradiation.

Plasma antioxidant activity was evaluated in the lecithin-Fe(2+) model system and cytogenetic studies were carried out in 16 men. A relationship between elevated antioxidant activity of the plasma and increased level of chromatid aberrations and with percentage of aberrant cells was detected in the experimental group, but no correlation was found between antioxidant activity and the integral dose of gamma-irradiation and rate of its accumulation. An assumption was made about exhaustion of the buffer capacity of the antioxidant defense system resulting from long-term exposure to unidentified factors of technogenic nature increasing plasma antioxidant activity and level of chromosome aberrations. In subjects with high level of antioxidant defense, naturally low antioxidant activity and low percentage of chromatid aberrations were probably maintained.

Antioxidant activity of blood plasma in individuals with neoplasms.

In 3 groups of patients with neoplasms plasma antioxidant activity was measured by the yield of TBA-reactive products generated in lecithin-Fe(2+) model system. Patients with laryngeal, tongue, oropharyngeal, oral, and laryngopharyngeal tumors showed lower plasma antioxidant activity compared to patients with breast, lung, and bronchial cancer (p<0.005). In women with breast cancer plasma antioxidant activity increased with age (p<0.05). Possible mechanisms underlying these fluctuations are discussed. It is assumed that plasma antioxidant activity is relatively stable and modulates body resistance to tumor process.