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Haplotype associations of 894 DNA samples of elderly people from the Russian population of Tomsk were analyzed using 49 SNPs (single nucleotide polymorphisms). As the analyzed markers, SNPs were selected that showed an association with Alzheimer’s disease or variability of cognitive abilities in genome-wide association studies. As a result of the analysis, blocks on chromosomes 1, 2, 6, 8, 11, 19, and 20 were identified. Significant associations were shown, taking into account 50 000 permutations, for haplotypes localized on chromosomes 1 and 19 in the genes CR1 and APOE, APOC1, respectively. Our results confirm the role of the APOE and CR1 genes in the pathogenesis of Alzheimer’s disease in the Russian population.

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.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.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).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.Цель исследования. Изучение связи rs11218343 гена сортилинподобного рецептора 1 (SORL1) с показателями состояния когнитивных функций у пожилых людей из российской популяции с диагнозом 'болезнь Альцгеймера' (БА) и без такового. Материал и методы. Выборка включала 586 пожилых пациентов (средний возраст 70,9±5,7 года) без БА и 100 пациентов с поздним началом БА (средний возраст 72,1±7,8 года) из популяции Томска. Генотипирование rs11218343 гена SORL1 проводили с помощью ПЦР и масс-спектрометрии. Нейропсихологическое тестирование проводили по Монреальской шкале оценки когнитивных функций (МоСА). Результаты. Частота аллелей rs11218343 гена SORL1 в изученных группах обследованных не достигала степени статистической достоверности. Однако средние значения общего балла по МоСА в контрольной выборке пожилых пациентов (без БА) у носителей редких аллелей отличались (были ниже) от гомозигот с частыми их вариантами (19,00±6,61 и 22,25±3,89; р0,026). Заключение. Редкий вариант в гене SORL1 связан с низкими показателями МоСА, о чем свидетельствует снижение когнитивных функций у носителей редкого аллеля в пожилом возрасте.

In contrast to the modest progress made in the interpretation and clinical application of genomic data, genotyping technologies have experienced great progress. Genotyping costs are progressively decreasing making individual genotyping more commonly available. Financial availability of individual genome analysis and the strong desire of many people to know about their individual genomic characteristics, promotes the marketing of genetic tests of variable predictive value directly to the public. A survey of 2000 Russian respondents revealed very positive attitudes and beliefs towards these genetic developments: 85% of surveyed individuals would like to have their genetic risk for avoidable diseases estimated, and 89% responded stating that they would try to change their lifestyle by giving up bad habits, following a recommended diet or taking medications if a high risk of disease was identified. It is believed that with time, validated genetic information will find its rightful place in medicine, by supplementing phenotypic clinical data with validated genetic interpretations.

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 Alzheimer’s 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 quartile’s 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.

Many new genetic tests for common multifactorial disorders are becoming available to individuals, including direct-to-consumer genotyping services. Typically, studies of public attitudes reveal a high level of interest for individual genotyping. In a Russian urban population, 85% of 2000 respondents answered positively to a question about their own willingness to undergo predictive genetic testing for preventable health conditions. Gender, age and health status significantly influenced response. Multivariate discriminant analyses revealed that wanting to know about probable future diseases, readiness to improve lifestyles and an interest in learning about individual genome characteristics are the most important predictors for wanting to be tested. Along with the high level of interest, highly overestimated expectations were encountered in many studies. With the low predictive abilities of currently available genetic tests for common disorders, proper interpretation of the data and genetic counseling are essential. There is a need for prospective validation of genetic panels for risk assessments, and for efforts to measure the effects of genetic information disclosure and how this information might contribute to lifestyle changes.

Understanding regional differences in cognitive performance is important for interpretation of data from large multinational clinical trials.Data from Durham and Cabarrus Counties in North Carolina, USA and Tomsk, Russia (n = 2972) were evaluated. The Montreal Cognitive Assessment (MoCA), Trail Making Test Part B (Trails B), Consortium to Establish a Registry for Alzheimer's Disease Word List Memory Test (WLM) delayed recall, and self-report Alzheimer's Disease Cooperative Studies Mail-In Cognitive Function Screening Instrument (MCFSI) were administered at each site. Multilevel modeling measured the variance explained by site and predictors of cognitive performance.Site differences accounted for 11% of the variation in the MoCA, 1.6% in Trails B, 1.7% in WLM, and 0.8% in MCFSI scores. Prior memory testing was significantly associated with WLM. Diabetes and stroke were significantly associated with Trails B and MCFSI.Sources of variation include cultural differences, health conditions, and exposure to test stimuli. Findings highlight the importance of local norms to interpret test performance.

The frequency of the polymorphic variant T196C (Leu33Pro, rs5918) of ITGB3 gene was studied in several groups of inhabitants of Siberia, including pregnant women with reproductive disorders (n = 186), patients with acute coronary syndrome (n = 330), and population control (n = 858). The frequency of the rare PLA2 allele among residents of Tomsk and Kemerovo was 14.7 and 15.0% respectively. There were no differences in the allele and genotype frequencies of polymorphic variant between patients with acute coronary syndrome and the control group (p = 0.925, p = 0.622). The highest frequency of abnormal PLA2 allele (22.1%) and the PLA2/PLA2 genotype (8.8%) was observed among women, who had miscarried, which was significantly different from the frequency of this allele and genotype in the control group (14.7%, p = 0.017; 2.1%, p = 0.0009). Sequencing showed that all samples with the nonspecific band had the polymorphic rs5918 variant and rs36080296 mutations (T216G, Leu66Arg). The frequency of the rs36080296 mutation among the residents of Siberia was 0.51%. Among the women with reproductive disorders, the frequency of rs36080296 was 2.7%, while in the group who suffered from miscarriages, it was 4.4%; this was different from the frequency in the control group (0.08%, p = 0.2 x 10(-6)). The accumulation of mutations was also observed among men with acute coronary syndrome (0.6%), but the differences from the control group (0%) had no statistical significance.