Analysis of Apolipoprotein E Gene Polymorphism in Populations of the Volga–Ural Region

Polymorphism at the apolipoprotein E gene (apoE) in populations of the Volga–Ural region was studied by means of polymerase chain reaction. In the region examined the population-specific patterns of the apoE alleles and genotypes frequency distribution were established. The results obtained were compared with the literature data on the apoE polymorphism in other world populations. Substantial heterogeneity of different ethnic populations in respect to the apoE genotypes distribution and frequency was revealed.     

Analysis of the Angiotensinogen Gene T174M Polymorphism in Populations of the Volga–Ural Region

The method of polymerase chain reaction was used to analyze T174M polymorphism at the angiotensinogen (AGT) gene in a number of populations of the Volga–Ural region, belonging to Finno–Ugric (Komi-Permyaks, Maris, Mordovians, and Udmurts), Turkic (Chuvashes, Tatars, and Bashkirs), and Eastern-Slavic (Russians) ethnic groups. Population-specific patterns of the polymorphic alleles and genotypes frequency distribution were established. Comparison of the results with the literature data on the AGT gene polymorphism in different world populations provided identification of specific trends in the changes of genotype frequency of the AGT gene depending on the ethnicity of the populations.     

Analysis of Polymorphisms of the Huntington Disease Gene in Ethnic Populations of the Volga–Ural Region

Eleven populations of the Volga–Ural region were analyzed with respect to three intragenic polymorphisms of the Huntington disease gene (IT15), including highly polymorphic (CAG)_n and moderately polymorphic (CCG)_n of exon 1 and neutral del2642 of exon 58. In the case of (CAG)_n, 101 genotypes were observed, with genotype number varying from 15 in Southeastern Bashkirs to 34 in Mari. Allele diversity R_S ranged from 9.70 in Southeastern Bashkirs to 18.00 in Chuvash, averaging 13.79 ± 2.12. The (CAG)_n allele frequency distribution was unimodal and had a maximum at (CAG)₁₇. In the case of (CCG)_n, six alleles with 6–12 repeats were observed. R_S was 4.13 ± 0.44, ranging from 3.73 in Udmurts to 4.99 in Tatars. In the case of del2642, allele del– was detected at a frequency 0.830 in Mari to 0.932 in Udmurts. Of all Volga–Ural ethnic populations, Finno-Ugric ones proved to be most heterogeneous with respect to the three polymorphisms, whereas Turkic populations and, in particular, Bashkirs were homogeneous. Microdifferentiation of the Volga–Ural populations corresponded to the European type.     

Polymorphism of Human Glutatione S-Transferase Gene in the Populations of the Volga–Ural Region

The frequency of the GstM1 gene deletion homozygotes in eight populations of the Volga–Ural region belonging according to linguistic classification to Turkic (Bashkirs, Tatars, and Chuvashs), Finno–Ugric (Maris, Komis, Mordovians, and Udmurts), and Eastern–Slavic (Russians) ethnic groups, was examined by means of PCR technique. The frequency of the deletion homozygotes varied from 41.4% in Bashkirs to 61.3% in Mordovians. The mean deletion frequency comprised 50.1%, which was consistent with the data for European populations (²= 0.009).     

Molecular Genetic Analysis of the DXS52Polymorphism in Populations of the Volga–Ural Region

The DXS52polymorphic locus mapping to the 5"-region of the blood-clotting factor VIII gene on the X chromosome was genotyped in seven Volga–Ural ethnic groups (Bashkirs, Tatars, Chuvashes, Maris, Mordovians, Udmurts, and Komis). A total of 47 different genotypes and 15 allelic variants of this locus were described. Substantial intra- and interpopulation heterogeneity of the ethnic groups studied in respect to frequency and distribution of the DXS52alleles and genotypes was demonstrated. The unimodal DXS52allele frequency distribution pattern with the peak at 1690 bp was typical to Mordovians and Komis. Chuvashes and Maris, as well as Udmurts, were characterized by bimodal frequency distribution patterns, with the peaks at 1690 and 670 bp, and 1690 and 1390 bp, respectively. Moreover, Bashkirs and Tatars displayed trimodal DXS52allele frequency distribution patterns with the peaks at 1690, 1390, and 670 bp. The DXS52allele frequency distribution patterns described in populations of the Volga– Ural region were found to be remarkably different from those established for the mixed Moscow population and the population of Western Europe. These data indicate that the DXS52locus is highly informative, and this polymorphic system can serve as a molecular marker for population genetic studies.     

Investigation of Monoamine Oxidase Gene Restriction Polymorphism in Male Populations of the Volga–Ural Region

Restriction polymorphism at the monoamine oxidase A (MAO A) gene was typed in eight male populations of the Volga– Ural region (Bashkirs, Chuvashes, Tatars, Udmurts, Maris, Mordovians, Komis, and Russians inhabiting the Republic of Bashkortostan). Analysis of the MAO A alleles frequency distribution patterns did not reveal statistically significant differences between the Volga–Ural populations examined. The results obtained suggest genetic homogeneity of the populations described in respect of the polymorphic locus examined.     

Polymorphism of Y-Chromosomal Diallelic Loci in Populations of the Volga–Ural Region

Three diallelic polymorphisms of human Y chromosome (DYS287(Y Alupolymorphism, YAP), T/C transition at the RBF5locus (Tat), and G/A transition at the LLY22locus) were studied in eight ethnic populations of the Volga–Ural region, representing Turkic branch of the Altai (Bashkirs, Tatars, and Chuvashes) and Finno-Ugric branch of the Uralic linguistic family (Maris, Mordovians, Udmurts, Komi-Zyryans, and Komi-Permyaks), and in the group of Slavic migrants, belonging to the Indo-European linguistic family (Russians). The Volga–Ural populations were characterized by a low frequency of the Y chromosome Aluinsertion. Examination of an association between the Alupolymorphism and Tatmutation revealed absolute YAP–/C linkage. Analysis of the haplotype frequency distribution patterns constructed from the data on the DYS287and RBF5polymorphisms revealed substantial differences between Udmurts and other populations. The differences were also observed between Komi-Zyryans and the populations of Bashkirs, Mordovians, Komi-Permyaks, and Russians. Analysis of the degree of genetic differentiation pointed to high level of genetic differentiation of the male lineages of the Finno–Ugric ethnic groups. The data on the linkage between the RBF5locus and the LLY22locus mutations indicated the common origin of the Tatmutationin Bashkirs, Mordovians, Udmurts, and Komi-Zyryans, and of a number of ancestralCallele-bearing Y chromosomes in Tatars, Maris, and Chuvashes.     

Investigation of Gene Insertion–Deletion Polymorphism of the Gene for Angiotensin-Converting Enzyme in Populations of the Volga–Ural Region

Insertion–deletion polymorphism at the angiotensin I-converting enzyme (ACE) gene in populations of the Volga–Ural region was examined by means of polymerase chain reaction. The populations studied belong to the Finno-Ugric (Komis, Maris, Mordovians, and Udmurts), Turkic (Chuvashes, Tatars, and Bashkirs), and Eastern-Slavic (Russians) ethnic groups. Distribution patterns of allele and genotype frequencies of this polymorphic system in the examined region were characterized. Comparison of the obtained results with the literature data on the ACE gene polymorphism in other Caucasoid and Mongoloid populations revealed some trends in the ACE genotype frequency dynamics depending on the ethnicity of the populations.     

A Study of the Insertion–Deletion Polymorphism of the Serotonin Transporter Gene in Populations from the Volga–Ural Region

The insertion–deletion polymorphism of the serotonin transporter gene (SLC6A4) was studied using the polymerase chain reaction (PCR) in eight populations from the Volga–Ural region (the Bashkir, Chuvash, Tatar, Udmurt, Mari, Mordovian, and Komi populations and the population of Russians living in the Arkhangel'skii raion of Bashkortostan). For this polymorphic system, the pattern of distribution of main population parameters was established in the region studied. Depending on population ethnicity, specific trends were revealed in the pattern of frequencies of alleles and genotypes of geneSLC6A4.     

Polymorphism of Hypervariable Segment I of Mitochondrial DNA in Three Ethnic Populations from the Volga–Ural Region

A population genetic study of the polymorphism in the first hypervariable segment (HVSI) of mitochondrial DNA control region was carried out for three ethnic populations of the Volga–Ural region, Bashkirs, Russians, and Komi-Permyaks. This analysis showed that most of the mtDNA HVSI haplotypes detected in the populations of Bashkirs, Russians and Komi-Permyaks contained the combinations of nucleotide substitutions detected earlier in European, and, to a lesser extent, Asian. These findings are consistent with historical, anthropological, and ethnographical data suggesting the presence of European and Mongoloid components of different geographical descent in the gene pool of the contemporary population of the Volga–Ural region. The data on the genetic structure and the phylogenetic relationships between populations of the Volga– Ural region based on modern molecular genetic methods of mitochondrial genome investigation would be a substantial addition to the already existing information for some other regions of Europe and Asia. These data would provide more complete examination of the development of interethnic diversity of mitochondrial gene pools of contemporary ethnic populations with the purpose of reconstructing the genetic demographic processes that accompanied peopling of the Middle Ural and Volga region.     

Diversity of Mitochondrial DNA Haplogroups in Ethnic Populations of the Volga–Ural Region

The mtDNA polymorphism was analyzed in eight ethnic groups (N = 979) of the Volga–Ural region. Most mtDNA variants belonged to haplogroups H, U, T, J, W, I, R, and N1 characteristic of West Eurasian populations. The most frequent were haplogroups H (12–42%) and U (18–44%). East Eurasian mtDNA types (A, B, Y, F, M, N9) were also observed. Genetic diversity was higher in Turkic than in Finno-Ugric populations. The frequency of mtDNA types characteristic of Siberian and Central Asian populations substantially increased in the ethnic groups living closer to the Urals, a boundary between Europe and Asia. Geographic distances, rather than linguistic barriers, were assumed to play the major role in distribution of mtDNA types in the Volga–Ural region. Thus, as concerns the maternal lineage, the Finno-Ugric populations of the region proved to be more similar to their Turkic neighbors rather than to linguistically related Balto-Finnish ethnic groups.     

Complex Analysis for Antiprotease–Protease Enzyme Gene Polymorphisms in Patients with Chronic Obstructive Pulmonary Diseases

A molecular genetic analysis of genes encoding the protease inhibitors ₁-antitrypsin (PI) and ₁-antichymotrypsin (AACT) was performed in patients with chronic obstructive pulmonary disease (COPD) (n = 239), cystic fibrosis (n = 57), and bronchiectasis (n = 33). In addition, the sample included children with chronic infant lung disease (n = 151) and nonobstructive chronic bronchitis (n = 34). Mutations Z and S of the ₁-antitrypsin gene (Glu342Lys and Glu264Val, respectively) resulting in severe enzyme deficiency and polymorphisms in the 3-untranslated region of the same gene (G1237A) and in the signal peptide for ₁-antichymotrypsin gene (Ala – 15Thr) were studied. No significant differences in the allele and genotype frequencies of these polymorphisms were revealed between the groups of patients and the control group. Promoter polymorphism G–1607GG in the interstitial collagenase gene (MMP1) was studied in patients with COPD, bronchiectasis, and chronic nonobstructive bronchitis. In COPD patients, the frequency of genotype GG/GG proved to be significantly higher than in the control group: 30.6 and 18.0%, respectively; ² = 6.58, p < 0.05; OR = 1.99 (95% CI 1.1–3.59). Thus, genetic polymorphism in the promoter of the MMP1 gene may be associated with an individual susceptibility to COPD.     

Do Epigenetic Events Take Place in the Vastus Lateralis of Patients with Mild Chronic Obstructive Pulmonary Disease?

Muscle dysfunction is a major comorbidity in Chronic Obstructive Pulmonary Disease (COPD). Several biological mechanisms including epigenetic events regulate muscle mass and function in models of muscle atrophy. Investigations conducted so far have focused on the elucidation of biological mechanisms involved in muscle dysfunction in advanced COPD. We assessed whether the epigenetic profile may be altered in the vastus lateralis of patients with mild COPD, normal body composition, and mildly impaired muscle function and exercise capacity. In vastus lateralis (VL) of mild COPD patients with well-preserved body composition and in healthy age-matched controls, expression of DNA methylation, muscle-enriched microRNAs, histone acetyltransferases (HTAs) and deacetylases (HDACs), protein acetylation, small ubiquitin-related modifier (SUMO) ligases, and muscle structure were explored. All subjects were clinically evaluated. Compared to healthy controls, in the VL of mild COPD patients, muscle function and exercise capacity were moderately reduced, DNA methylation levels did not differ, miR-1 expression levels were increased and positively correlated with both forced expiratory volume in one second (FEV₁) and quadriceps force, HDAC4 protein levels were increased, and muscle fiber types and sizes were not different. Moderate skeletal muscle dysfunction is a relevant feature in patients with mild COPD and preserved body composition. Several epigenetic events are differentially expressed in the limb muscles of these patients, probably as an attempt to counterbalance the underlying mechanisms that alter muscle function and mass. The study of patients at early stages of their disease is of interest as they are a target for timely therapeutic interventions that may slow down the course of the disease and prevent the deleterious effects of major comorbidities.     

Polymorphism of the Tumor Necrosis Factor α Gene in Patients with Infiltrative Tuberculosis from the Bashkortostan Populations

The polymorphism at position –308 of the TNF- gene promoter was analyzed in three ethnic groups and in patients with infiltrative pulmonary tuberculosis from Bashkortostan. No interethnic difference in allele or genotype frequency distribution was observed. The frequency of allele TNF2 in tuberculosis patients was significantly higher than in controls (² = 11.69, p = 0.001), suggesting association of this allele with higher risk of pulmonary tuberculosis or with markedly disturbed immune response.     

Circadian‐Rhythm Differences among Emergency Department Patients with Chronic Obstructive Pulmonary Disease Exacerbation

The purpose of the study was determine whether patients with chronic obstructive pulmonary disease (COPD) exacerbation who present to the emergency department (ED) during the night (00:00 to 07:59 h) vs. other times of the day have more severe COPD exacerbation, require more intensive treatment, and have worse clinical outcomes. A multicenter cohort study was completed involving 29 EDs in the United States and Canada. Using a standard protocol, consecutive ED patients with COPD exacerbation were interviewed, and their charts were reviewed. Of 582 patients enrolled, 52% were women, and the median age was 71 yrs (interquartile range, 64–77 yrs). Nighttime patients (15% of cohort) did not differ from patients presenting at other times except that they were less likely to have private insurance, more likely to have a history of corticosteroid use, and have a shorter duration of symptoms exacerbation. Except for a few features indicative of more severe COPD exacerbation (such as higher respiratory rate at ED presentation, greater likelihood of receiving noninvasive positive pressure ventilation, and increased risk of endotracheal intubation), nighttime patients did not differ from other patients with respect to ED management. Nighttime patients were approximately three‐fold more likely to be intubated in the ED (odds ratio, 3.46; 95% confidence interval, 1.10–10.9). There were no day‐night differences regarding ED disposition and post‐ED relapse. Except for some features indicating more severe exacerbation, nighttime ED patients had similar chronic COPD characteristics, received similar treatments in the ED, and had similar clinical outcomes compared with patients presenting to the ED at other times of the day.     

“Sentinel” Circulating Tumor Cells Allow Early Diagnosis of Lung Cancer in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a risk factor for lung cancer. Migration of circulating tumor cells (CTCs) into the blood stream is an early event that occurs during carcinogenesis. We aimed to examine the presence of CTCs in complement to CT-scan in COPD patients without clinically detectable lung cancer as a first step to identify a new marker for early lung cancer diagnosis. The presence of CTCs was examined by an ISET filtration-enrichment technique, for 245 subjects without cancer, including 168 (68.6%) COPD patients, and 77 subjects without COPD (31.4%), including 42 control smokers and 35 non-smoking healthy individuals. CTCs were identified by cytomorphological analysis and characterized by studying their expression of epithelial and mesenchymal markers. COPD patients were monitored annually by low-dose spiral CT. CTCs were detected in 3% of COPD patients (5 out of 168 patients). The annual surveillance of the CTC-positive COPD patients by CT-scan screening detected lung nodules 1 to 4 years after CTC detection, leading to prompt surgical resection and histopathological diagnosis of early-stage lung cancer. Follow-up of the 5 patients by CT-scan and ISET 12 month after surgery showed no tumor recurrence. CTCs detected in COPD patients had a heterogeneous expression of epithelial and mesenchymal markers, which was similar to the corresponding lung tumor phenotype. No CTCs were detected in control smoking and non-smoking healthy individuals. CTCs can be detected in patients with COPD without clinically detectable lung cancer. Monitoring “sentinel” CTC-positive COPD patients may allow early diagnosis of lung cancer.     

Adjunctive Treatment with Rhodiola Crenulata in Patients with Chronic Obstructive Pulmonary Disease – A Randomized Placebo Controlled Double Blind Clinical Trial

Chronic obstructive pulmonary disease (COPD) is a low grade systemic inflammatory disease characterized by dyspnea and exercise intolerance even under standard therapy. Rhodiola crenulata (RC) has been shown to exert anti-inflammatory effects and to enhance exercise endurance, thereby having the potential to treat COPD. In this 12-week, randomized, double-blind, placebo-controlled clinical trial, 57 patients with stable moderate-to-severe COPD aged 70±8.8 years were given RC (250 mg twice/day) (n=38) or a placebo (250 mg twice/day) (n=19) in addition to their standard regimen. There were no significant differences in anthropometrics, quality of life, lung function, six-minute walk and incremental exercise tests between the two groups at enrollment. Over the 12 weeks, RC was well tolerated, significantly reduced triceps skin thickness (Δ=-1 mm, p=.04), change of FEV1 (4.5%, p=.03), and improved workload (Δ=10%, p=.01); although there were no significant differences in these factors between the two groups. However, there were significant between-group differences in tidal volume and ventilation-CO₂-output ratio at peak exercise (both p=.05), which were significantly related to peak work rate (both p<.0001). RC tended to protect against acute exacerbation of COPD (p=.1) but not other measurements. RC did not improve the six-minute walk test distance but significantly improved tidal breathing and ventilation efficiency, most likely through improvements in work rate. Further studies with a larger patient population are needed in order to confirm these findings.

Trial Registration

ClinicalTrials.gov number NCT02242461     

The Structure of the Gene Pools of the Ethnic Populations of Altai–Sayan Region Based on of Mitochondrial DNA Polymorphism Data

Using the data on mitochondrial DNA (mtDNA) polymorphism, genetic structures of the four Turkic-speaking ethnic groups of Altai–Sayan highlands, Southern Altaians (Altai- Kizhi), Khakassians, Shorians, and Sojots, were described. Mitochondrial gene pools of the populations examined were characterized by different ratios between Mongoloid (M*, C, D, E, G, A, B, and F) and Caucasoid (H, U, T, J, and K) mtDNA lineages. All the populations studied had a strongly pronounced Mongoloid component, the frequency of which was 88.2% in Sojots, 75.9% in Khakassians, 67.4% in Altaians, and 64.3% in Shorians. Maximum frequency of the Caucasoid component (35.7%) was observed in Shorians. Phylogenetic and statistical analyses of the mtDNA group frequency distribution patterns in the gene pools of the ethnic populations of Altai–Sayan highlands and the adjacent territories showed that the populations of the region fell into three groups. The first group included Khakassians, Tuvinians and Altaians, the second group consisted of Sojots, Buryats, and Mongols, while the third group was composed of Uigurs, Kazakhs, and Kyrgyzes. The isolated position of Shorians among the populations examined can be explained by their different anthropological composition and their presumptive relatedness to Finno-Ugric populations of Siberia.     

Testing for Linkage and Association Across the Dihydrolipoyl Dehydrogenase Gene Region with Alzheimer’s Disease in Three Sample Populations

Prior case-control studies from our laboratory of a population enriched with individuals of Ashkenazi Jewish descent suggested that association exists between Alzheimer's disease (AD) and the chromosomal region near the DLD gene, which encodes the mitochondrial dihydrolipoamide dehydrogenase enzyme. In support of this finding, we found that linkage analysis restricted to autopsy-proven patients in the National Institute of Mental Health-National Cell Repository for Alzheimer's Disease (NIMH-NCRAD) Genetics Initiative pedigree data resulted in point-wise significant evidence for linkage (minimum p-value = 0.024) for a marker position close to the DLD locus. We now report case-control replication studies in two independent Caucasian series from the US and Italy, as well as a linkage analysis from the NIMH-NCRAD Genetics Initiative Database. Pair-wise analysis of the SNPs in the case-control series indicated there was strong linkage disequilibrium across the DLD locus in these populations, as previously reported. These findings suggest that testing for association of complex diseases with DLD locus should have considerable statistical power. Analysis of multi-locus genotypes or haplotypes based upon three SNP loci combined with results from our previous report provided trends toward significant evidence of association of DLD with AD, although neither of the present studies' association showed significance at the 0.05 level. Combining linkage and association findings for all AD patients (males and females) results in a p-value that is more significant than any of the individual findings' p-values. Finally, minimum sample size calculations using parameters from the DLD locus suggest that sample sizes on the order of 1,000 total cases and controls are needed to detect association for a wide range of genetic model parameters.