[Combination of Genetic and Humanitarian (Cross-Cultural) Methods for the Identification of Human Genes Involved in the Process of Adaptation to Evolutionary New Environmental Factors].

Human settlement from the African ancestral home was accompanied by cultural and genetic adaptation to new habitat conditions (climate, infections, diet, etc.). We previously suggested for the first time an approach to the identification of human genes presumably involved in adaptation to evolutionary new environmental factors based on a combination of genetic and humanitarian methods of study. In order to search for the genes involved in adaptation and for environmental factors (to which this adaptation occurs), we attempted to find correlations between the population allele frequencies of the studied gene and formalized descriptions of peculiarities of the habitat of ethnic groups given in "Ethnographic Atlas" by G. P. Murdock. In the presented review, we summarized our own data on an experimental determination of the allele frequencies for lactase (LCT*), apolipoprotein E (APOE), and alcohol dehydrogenase (ADH1B) genes in populations of Russia. Based on these data and available materials of other investigators, we developed maps of worldwide allele frequency distribution for these genes. We detected a correlation of allele frequencies of these genes in populations with the presence of certain factors of the environment that these populations inhabit. It was also confirmed that the evolutionarily young LCT*-13910T allele, which determines lactase persistence and the possibility of milk consumption in adults, is distributed in populations for which dairy animal husbandry is typical. During the analysis of 68 populations, we for the first time demonstrated that the frequency of the APOE e4 allele (which is ancestral for humans and influences the lipid metabolism) is higher in groups with a high contribution of hunting and gathering. Our data are in favor of the hypothesis that it was exactly the e4 allele that was a subject for selection, while the e3 allele was less important for adaptation. We also for the first time demonstrated that the evolutionarily young ADH1B*48His allele (which determines a high rate of ethanol metabolism into acetaldehyde) is presented with a large frequency in those populations where filariasis is endemic. The obtained data indicate the possible involvement of endogenous ADH1B gene substrates or their metabolites in the resistance to filaria and open a new path to the development of drugs for this widespread human disease.

The Impact of ADH1B Alleles and Educational Status on Levels and Modes of Alcohol Consumption in Russian Male Individuals.

Alcohol abuse is one of the main reasons behind the low life span in Russia. Both social and genetic factors affect the alcohol consumption level. The genetic factors are alleles of the alcohol dehydrogenase ADH1B and aldehyde dehydrogenaseALDH2 genes. We have typed and found frequencies for the alleles in a cohort of 642 men, ethnic Russians. The individuals of the cohort were asked to complete a questionnaire in the framework of the Izhevsk Family Study (Leon et al., 2007, 2009) regarding the amount of alcohol consumed and on the type of hazardous alcohol consumption (nonbeverage alcohol consumption and the so-called "zapoï" which is a Russian term for a heavy drinking bout lasting for at least 2 days, when an individual is withdrawn from the normal social life). The ADH1B*48His allele was found among heterozygous individuals only (N=68, 10.6% of the cohort). The ALDH2*504Lys allele was also found among heterozygous individuals only (N=2, 0.3%) The effect of ADH1B alleles and the influence of the education level on the amount and type of alcohol consumed had not previously been studied in Russians. We have found that the amount of consumed alcohol is 21.6% lower (1733 g of ethanol per year) for ADH1B*48His allele carriers in the cohort of Russian men. The amount of consumed alcohol was found to be 9.8% lower (793 g of ethanol per year) in the case when individuals had a higher education as compared to those who had a secondary- or elementary school education level in the same cohort. Hence, the protective effect of the genetic factor (ADH1B*48His allele carriage) has proven to be more pronounced than the influence of the social factor (education level) at the individual level in the cohort of Russian men. Both factors have also proven to have a protective effect against hazardous types of alcohol consumption. Zapoï was not scored among individuals of the cohort with ADH1B*48His allele carriage (OR=12.6, P=0.006), as compared to 8.4% of "zapoï" individuals who did not carry the ADH1B*48His allele (genotype Arg/Arg).The percentage of individuals who consume non-beverage alcohol is lower (0.6%) in the subcohort of people with a higher education degree. This percentage is higher (6.0%, OR=10.0, P=0.004) in the subcohort of people without a higher education degree.

[Allele frequency distributions of -174G/C polymorphism in regulatory region of interleukin 6 gene (IL6) in Russian and worldwide populations].

Allele and genotype frequencies of the -174G/C polymorphism (rs1800795) in the regulatory region of the IL6 gene, which encode anti-inflammatory cytokine interleukin 6, were determined in seven populations representing five ethnic groups from the European part of Russia (440 individuals), as well as in small cohorts that represent populations from 24 countries of Africa and Eurasia (365 individuals). The maps of the geographic distribution of the -174G/C allele frequencies were constructed based on personal (22 populations) and the literature data (66 populations), and the data from dbSNP database obtained by the HapMap project (10 populations). The frequency of the -174G allele varied from 45 to 100% and was characterized by nonrandom geographic distribution. These data could reflect the adaptive load of the alleles examined, which was different in different regions of the world. It is suggested that the level of pathogen prevalence is one of the environmental factors that determine different adaptive values of the IL6*--174G/C alleles. This suggestion is supported by a positive correlation between the -174G allele frequency and level of pathogen prevalence calculated based on historical data (R = 0.768; p < 0.0001).

Risk of HIV Infection and Lethality Are Decreased in CCR5del32 Heterozygotes: Focus Nosocomial Infection Study and Meta-analysis.

CCR5del32 Homozygous deletion in the chemokine receptor R5 gene provides almost complete protection to individuals against HIV infection. However, data relating to the protective effect forCCR5del32 heterozygous individuals have been contradictory. The frequency of theCCR5del32allele in population control cohorts was compared with that of a group of children (27 Kalmyks and 50 Russians) infected by G-subtype HIV-1 in a nosocomial outbreak. The frequency of theCCR5del32allele was shown to be lower among the infected children in comparison with that of the control group; however, the difference was small and statistically insignificant. Similar results were obtained in a number of earlier studies. The insignificance of the small differences could be a result of one of two reasons. (i) The fact that there is no protective effect of the heterozygous state, and that the phenomenon depends only on the fluctuation of allele frequencies. In this case, there would be no differences even if the infected cohort is enlarged. (ii)The protective effect of the heterozygous state is real; however, the size of the studied cohort is insufficient to demonstrate it. In order to discern between these two reasons, a meta-analysis of data from 25 published articles (a total of 5,963 HIV-infected individuals and 5,048 individuals in the control group, including the authors' own data) was undertaken. A conclusion was drawn from the meta-analysis that theCCR5del32 allele protects individuals against the HIV infection even in a heterozygous state (OR=1.22, 95%CI=1.10-1.36). The risk of HIV infection forCCR5 wt/del32 heterozygotes was lower by at least 13% as compared to that for wild typeCCR5 wt/wthomozygotes. Prior to this study, no data of the type or any conclusions had been published for Caucasians. The mortality rate in the 15 years following the infection was found to be approximately 40% lower forCCR5del32 heterozygotes in comparison with that for the wild type homozygotes in the studied group. The size of the studied group was insufficient to claim difference validity (OR=2.0;p= 0.705), even though the effect quantitatively matched the published data. The features of the meta-analysis influencing the threshold level and the statistical validity of the effects are being discussed. The level of theCCR5del32 protective effect on the chances to be infected with HIV and on the outcome of the HIV infection was assessed for various ethnic groups.

Association of cytokine gene alleles with the inflammation of human periodontal tissue.

Gingivitis and periodontitis are chronic inflammatory diseases of the periodontal tissue in humans caused by both environmental and genetic factors. The human cytokine genes that regulate the immune response may play an important role in the development of these chronic inflammatory diseases. The aim of this study is to analyze the allele status of eight human cytokine genes and to associate it with the inflammation of periodontal tissue in humans. A total of 296 unrelated males of Russian origin were studied. A significant association of theIL1BandIL6 minor alleles and gingivitis was found. In addition, we found a significant association of the OHI-S index with theIL18gene alleles. The influence of genetic factors on gingivitis may contribute to the understanding of the mechanisms of interaction between genetic and environmental factors in periodontal conditions, and to the identification of risk groups for effective prevention and treatment.

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.

Achievements and peculiarities in studies of ancient DNA and DNA from complicated forensic specimens.

Studies of ancient DNA specimens started 25 years ago. At that time short mitochondrial DNA (mtDNA) fragments were the main targets in ancient DNA studies. The last three years were especially productive in the development of new methods of DNA purification and analysis. Complete mtDNA molecules and relatively large fragments of nuclear DNA are the targets of ancient DNA studies today. Ancient DNA studies allowed us to study organisms that went extinct more than ten thousand years ago, to reconstruct their phenotypic traits and evolution. Ancient DNA analyses can help understand the development of ancient human populations and how they migrated. A new evolutionary hypothesis and reconstruction of the biota history have been re-created from recent ancient DNA data. Some peculiarities and problems specific to the study of ancient DNA were revealed, such as very limited amounts of DNA available for study, the short length of the DNA fragments, breaks and chemical modifications in DNA molecules that result in "postmortem" mutations or complete blockage of DNA replication in vitro. The same specific features of DNA analysis were revealed for specimens from complicated forensic cases that result in the lack of experimental data or interpretation problems.. Here, we list the specific features of ancient DNA methodology and describe some achievements in fundamental and applied research of ancient DNA, including our own work in the field.

Recombinant Listeria strains producing the nontoxic L-chain of botulinum neurotoxin A in a soluble form.

Fragments of Clostridium botulinum neurotoxin A (BoNT/A) gene (botA) were expressed in Listeria monocytogenes ATCC10527 to produce the L-chain of the toxin in a soluble form. A shuttle vector pAT19 (EmR) was used to make plasmid pAT-RL containing a botA gene fragment placed under C. botulinum ntnH-gene promoter control. The plasmid also contained a C. botulinum botR/A gene, a positive transcriptional regulator of botA. The cytoplasmic fraction of the L. monocytogenes (pAT-RL) strain was found to contain up to 3 mg/L of a soluble protein of expected size and immunologically positive towards BoNT antibodies. This is the first evidence of heterologous botA gene expression producing a soluble safe derivative of botulinum neurotoxin A needed as a molecular tool for exploratory research in neurosciences as well as a basis for raising protective immunity in humans.