Role of PI3K/AKT/mTOR signaling pathway and sirtuin genes in chronic obstructive pulmonary disease development.

Chronic obstructive pulmonary disease (COPD) is a multifactorial disease of the respiratory system which develops as a result of a complex interaction of genetic and environmental factors closely related to lifestyle. We aimed to assess the combined effect of the PI3K/AKT/mTOR signaling pathway (PIK3R1, AKT1, MTOR, PTEN) and sirtuin (SIRT1, SIRT3, SIRT6) genes to COPD risk. SNPs of SIRT1 (rs3758391, rs3818292), SIRT3 (rs3782116, rs536715), SIRT6 (rs107251), AKT1 (rs2494732), PIK3R1 (rs10515070, rs831125, rs3730089), MTOR (rs2295080, rs2536), PTEN (rs701848, rs2735343) genes were genotyped by real-time polymerase chain reaction (PCR) among 1245 case and control samples. Logistic regression was used to detect the association of SNPs in different models. Linear regression analyses were performed to estimate the relationship between SNPs and lung function parameters and smoking pack-years. Significant associations with COPD were identified for SIRT1 (rs3818292) (P = 0.001, OR = 1.51 for AG), SIRT3 (rs3782116) (P = 0.0055, OR = 0.69) and SIRT3 (rs536715) (P = 0.00001, OR = 0.50) under the dominant model, SIRT6 (rs107251) (P = 0.00001, OR = 0.55 for СT), PIK3R1: (rs10515070 (P = 0.0023, OR = 1.47 for AT), rs831125 (P = 0.00001, OR = 2.28 for AG), rs3730089 (P = 0.0007, OR = 1.73 for GG)), PTEN: (rs701848 (P = 0.0015, OR = 1.35 under the log-additive model), and rs2735343 (P = 0.0001, OR = 1.64 for GC)). A significant genotype-dependent variation of lung function parameters was observed for SIRT1 (rs3818292), SIRT3 (rs3782116), PIK3R1 (rs3730089), and MTOR (rs2536). Gene-gene combinations that remained significantly associated with COPD were obtained; the highest risk of COPD was conferred by a combination of G allele of the PIK3R1 (rs831125) gene and GG of SIRT3 (rs536715) (OR = 3.45). The obtained results of polygenic analysis indicate the interaction of genes encoding sirtuins SIRT3, SIRT2, SIRT6 and PI3KR1, PTEN, MTOR and confirm the functional relationship between sirtuins and the PI3K/AKT/mTOR signaling pathway.

[Current state of the obesity research: genetic aspects, the role of microbiome, and susceptibility to COVID-19].

Obesity affects over 700 million people worldwide and its prevalence keeps growing steadily. The problem is particularly relevant due to the increased risk of COVID-19 complications and mortality in obese patients. Obesity prevalence increase is often associated with the influence of environmental and behavioural factors, leading to stigmatization of people with obesity due to beliefs that their problems are caused by poor lifestyle choices. However, hereditary predisposition to obesity has been established, likely polygenic in nature. Morbid obesity can result from rare mutations having a significant effect on energy metabolism and fat deposition, but the majority of patients does not present with monogenic forms. Microbiome low diversity significantly correlates with metabolic disorders (inflammation, insulin resistance), and the success of weight loss (bariatric) surgery. However, data on the long-term consequences of bariatric surgery and changes in the microbiome composition and genetic diversity before and after surgery are currently lacking. In this review, we summarize the results of studies of the genetic characteristics of obesity patients, molecular mechanisms of obesity, contributing to the unfavourable course of coronavirus infection, and the evolution of their microbiome during bariatric surgery, elucidating the mechanisms of disease development and creating opportunities to identify potential new treatment targets and design effective personalized approaches for the diagnosis, management, and prevention of obesity.

[Association of adiponectin gene alleles with type 2 diabetes mellitus in residents of Bashkortostan].

Type 2 diabetes mellitus (T2DM) is one of the most acute problems of the modern world. The disease is characterized by high ratio of micro- and macrovascular complications. T2DM is a multifactorial and polygenic disease, structure of hereditary predisposition to which may be population-specific. Aim - the analysis of allelic associations of adiponectin gene (ADIPOQ, rs17366743) with T2DM, its clinical and metabolic characteristics and complications in T2DM patients resident in the Republic of Bashkortostan. MATERIAL AND METHODS: 3 PCR-based method of genotyping with polymorphic marker rs17366743 of ADIPOQ gene in 433 T2DM patients and 428 healthy controls, residents of Bashkortostan. RESULTS: The ratio of genotype CT and allele С was higher in T2DM patients compared with controls (15.7% vs. 6.8%; p=0.0002 and 7.8% vs. 3.4%; p<0.0001, respectively). Genotype ТТ and allele Т were less frequent in T2DM than in healthy subjects (84.3 and 93,2%; p=0.0002; 92.2 and 96.6%, p<0.0001, respectively). The association with the development of diabetic retinopathy and cataract was shown (p=0,044, p=0,008, respectively). CONCLUSIONS: Allele C and genotype CT are risk markers of T2DM (OR=2.43 and 2.56 respectively).

[Polymorphic Variants of Glutamate Receptor (GRIK5, GRIN2B) and Serotonin Receptor (HTR2A) Genes Are Associated with Chronic Obstructive Pulmonary Disease].

Chronic obstructive pulmonary disease (COPD) is a complex chronic inflammatory disease of the respiratory system that affects primarily distal respiratory pathways and lung parenchyma. Smoking tobacco is a major risk factor for COPD. The relationship of HTR4 (rs3995090), HTR2A (rs6313), GRIK5 (rs8099939), GRIN2B (rs2268132), and CHRNB4 (rs1948) gene polymorphisms and COPD, as well as the contribution of these polymorphisms to the variations in quantitative characteristics that describe respiratory function, smoking behavior, and nicotine dependence was assessed in an ethnically homogeneous Tatar population. The polymorphisms of HTR2A (rs6313) (P = 0.026, OR = 1.42 for the CC genotype) and GRIN2B (rs2268132) (P = 0.0001, OR = 2.39 for the TT genotype) were significantly associated with increased risk of COPD. The AA genotype of GRIK5 (rs8099939) had a protective effect (P = 0.02, OR = 0.61). Importantly, the HTR2A (rs6313), GRIN2B (rs2268132), and GRIK5 (rs8099939) polymorphisms were only associated with COPD in smokers. Smoking index (pack-years) was significantly higher in carriers of the GRIK5 genotype AC (rs8099939) (P = 0.0027). The TT genotype of GRIN2B (rs2268132) was associated with COPD in subjects with high nicotine dependence according to the Fagerstrõm test (P = 0.002, OR = 2.98). The TT genotype of HTR2A (rs6313) was associated with a reduced risk of the disease in the group with moderate nicotine dependence (P = 0.02, OR = 0.22). The CC genotype of HTR2A (rs6313) and the TT genotype of GRIN2B (rs2268132) were associated with higher levels of nicotine dependence according to the Fagerstrõm test (P = 0.0011 and P = 0.037). Our results may provide insight into potential molecular mechanisms that involve the glutamate (GRIK5, GRIN2B) and serotonin (HTR2A) receptor genes in the pathogenesis of COPD.

Inflammatory and Immune Response Genes Polymorphisms are Associated with Susceptibility to Chronic Obstructive Pulmonary Disease in Tatars Population from Russia.

Chronic obstructive pulmonary disease (COPD) is a complex chronic inflammatory disease of the respiratory system affecting primarily distal respiratory pathways and lung parenchyma. This work was designed as a case-control study aimed at investigating the association of COPD with polymorphisms in inflammatory and immune response genes (JAK1, JAK3, STAT1, STAT3, NFKB1, IL17A, ADIPOQ, ADIPOR1, etc.) in Tatar population from Russia. Ten SNPs (rs310216, rs3212780, rs12693591, rs2293152, rs28362491, rs4711998, rs1974226, rs1501299, rs266729, and rs12733285) were genotyped by the real-time polymerase chain reaction (TaqMan assays) in a case-control study (425 COPD patients and 457 in the control group, from Ufa, Russia). Logistic regression was used to detect the association of SNPs in different models. Linear regression analyses were performed to estimate the relationship between SNPs and lung function parameters and pack-years. In Tatar population, significant associations of JAK1 (rs310216) (P = 0.0002, OR 1.70 in additive model), JAK3 (rs3212780) (P = 0.001, OR 1.61 in dominant model), and IL17A (rs1974226) (P = 0.0037, OR 2.31 in recessive model) with COPD were revealed. The disease risk was higher in carriers of insertion allele of NFKB1 (rs28362491) (P = 0.045, OR 1.22). We found a significant gene-by-environment interaction of smoking status and IL17A (rs1974226) (P interact = 0.016), JAK3 (rs3212780) (P interact = 0.031), ADIPOQ (rs266729) (P interact = 0.013), and ADIPOR1 (rs12733285) (P interact = 0.018). The relationship between the rs4711998, rs1974226, rs310216, rs3212780, rs28362491, and smoking pack-years was found (P = 0.045, P = 0.004, P = 0.0005, P = 0.021, and P = 0.042). A significant genotype-dependent variation of forced vital capacity was observed for NFKB1 (rs28362491) (P = 0.017), ADIPOR1 (rs12733285) (P = 0.043), and STAT1 (rs12693591) (P = 0.048). The genotypes of STAT1 (rs12693591) (P = 0.013) and JAK1 (rs310216) (P = 0.048) were associated with forced expiratory volume in 1 s.

[Association of variable rs1801282 locus of PPARG2 gene with diabetic nephropathy].

The association of the variable rs1801282 locus of the PPARG2 gene (peroxisome proliferator-activated receptor gamma) with type 2 diabetes mellitus and its complications was analyzed in inhabitants of the Republic of Bashkortostan. The genotype frequencies of the variable rs1801282 locus of the PPARG2 gene did not significantly differ in groups of healthy persons and patients with type 2 diabetes in all three considered inheritance models (codominant, dominant, and recessive). At the same time, it was demonstrated that the risk of one of the diabetic complications, i.e., diabetic nephropathy, was associated with the variable rs1801282 locus of the PPARG2 gene. Diabetic nephropathy was more common in patients with the C/C genotype (62.7%) compared to the C/G and G/G genotypes (37.5%), P = 0.036. The G allele is protective in regard to diabetic nephropathy (OR = 0.36) in patients with type 2 diabetes mellitus.

[Genetic Association of ADRA2A and ADRB3 Genes with Metabolic Syndrome among the Tatars].

An association study was performed for genetic polymorphisms in ADRB3 (rs4994) and ADRA2A (rs1800544, rs553668) genes to estimate their effect on quantitative parameters, including glucose, insulin, and HOMA-IR index in women from the Tatar population of Russia. It has been shown that CT and CC are associated with metabolic syndrome and increased insulin. It was shown that ADRA2A (rs1800544) gene polymorphism was associated with high levels of insulin and an increased HOMA-IR index in GG- and GC-genotype carriers.

[Association of polymorphic variants of FTO and MC4R genes with obesity in a Tatar population].

Obesity is a chronic relapsing disease that leads to numerous ailments and requires lifelong treatment. Genetic predisposition is one of the mostly discussed aspects of obesity development, and genome-wide association studies have provided evidence that several variants of the FTO and MC4R genes are significantly associated with obesity. In this study the association of FTO (rs9939609, rs7202116, and rs9930506) and MC4R (rs12970134 and rs17782313) genes' SNPs with obesity in Tatar women has been analyzed. In the investigation 340 women with obesity (Body Mass Index (BMI) ≥ 30 kg/m2) and 330 women from a control group (BMI up to 24.9 kg/m2) took part. The FTO rs9939609 (p = 0.0002) and rs9930506 (p = 0.0005) SNPs were shown to be associated with obesity risk following an additive model, while the MC4R rs12970134 (p = 0.0076) and rs1778231 (p = 0.021) SNPs were associated by a recessive model. We also showed an association of quantitative parameters (age, weight, and BMI) with two the FTO rs9939609 and rs9930506 SNPs and the association of age and the MC4R rs12970134 SNP. Our study demonstrates the role of genetic variability in FTO and MC4R genes in obesity development in Tatar women from Russia.

[DIO2, TPO, CYP1A1 AND CYP1A2 gene polymorphism in women with thyroid disease].

The analysis of polymorphisms of genes CYP1A1 (2454A > G,-3798T> C); CYP1A2 (-163C > A,-2467delT); TPO (2173A > C, 769G > T); DIO2 (274A > G) in women from the oil organic synthesis plant and the control group with thyroid disease (autoimmune thyroiditis and nodular goiter) has been performed. Molecular genetic markers of predisposition to the development of thyroid disease are: GG genotype and allele G gene DIO2 (274A > G), CT and CC genotypes of the gene CYP1A1 (-3798T > C), associated with the development of nodular goiter, and DD genotypes TD CYP1A2 gene (-2467delT), associated with the development of autoimmune thyroiditis. There was shown an association of polymorphic variants of the gene DIO2 (274A > G) with elevated levels of antibodies to TPO and TPO gene (2173A > C) with elevated levels of free T4.

[DNA repair XRCC1, XPD genes polymorphism as associated with the development of bladder cancer and renal cell carcinoma].

We examined the correlations between the polymorphic alleles of the DNA repair genes XRCC1 (c.839G> A, rs25489; and c.1196A> G, rs25487), XPA (c.-4A> G, rs1800975), and XPD (c.2251A> C, rs13181) and the progression and severity of neoplasias in the bladder and kidney in patients of three distinct ethnic groups, Bashkir, Russians, and Tatar, residing in the Republic of Bashkorostan. The study enrolled 468 cancer patients and 351 healthy individuals. Genotyping for polymorphic alleles was carried out using the PCR-RFLP method. We identified a correlation between allele A of the c.839 G>A locus of the XRCC1 gene and the incidence of the bladder cancer (BC) and kidney cancer (KC) in the Tatar study group, using the additive genetic effects model (Odds Ratio (OR) = 5.23 and OR = 3.90). In turn, the heterozygous G/A genotype was present at a significantly higher frequency in the KC patients of Bashkir ethnic origin, compared with the control group (p = 0.0061, OR= 4.72). Additional analysis with consideration of participants' smoking status showed that the G/A genotype is significantly more frequent in smokers with BC (OR = 1.96, p = 0.05) then in healthy smokers. We also determined, using the recessive genetic model, that the genotype A/A of the c. 1196A>G locus of the XRCC1 gene was correlated with a higher risk of BC in the Russian cohort (OR = 2.29, p = 0.0082) and an increased incidence of KC in the Bashkir group (OR = 4.06, p = 0.05). A similar correlation was obtained for smokers. In contrast, the allele c.2251 A>C in the XPD gene correlated with a lower risk for BC and KC in the Tatars (p = 0.0003, OR = 0.48 and p < 0.0001, OR = 0.37) in the additive model and in the Bashkirs (p = 0.0083, OR = 0.12) and Russians (p = 0.0001, OR = 0.14) in the recessive model. Further, we uncovered that polymorphism c.839 G>A in the XRCC1 gene contributes to the progression of noninvasive and invasive BC and promotes KC at early and advanced stages of the disease. Thus, we identified similar correlations between DNA repair gene polymorphism and the incidence and progression of BC and KC. We propose that this result points to the involvement of common pathogenetic mechanisms in the initiation and progression of the urinary neoplasias.

[Age-dependent CYP1A2 gene polymorphism -163C>A in three ethnic groups of Bashkortostan Republic residents].

On a sample of 1240 persons from Bashkortostan, including Russian, Bashkirs and Tatars, the analysis of allele and genotype frequencies distribution of CYP1A2 gene polymorphism -163C>A was performed by PCR-RFLP in view of belonging to a particular age cohort. In Russian and Bashkirs ethnic groups we observed age-dependent decrease of CYP1A2*C allele and CYP1A2*CI*C genotype frequencies (in Russian statistically significant for allele and genotype, the Bashkirs--only for allele) and a statistically significant increase of CYP1A2*A allele and CYP1A2*A/*A genotype frequencies. The set reduction in the frequency of the wild allele CYP1A2*C and increasing the frequency of the mutant allele CYP1A2*A with age may be due to greater survival of persons who are carriers of that allelic variants of CYP1A2 gene, providing a more efficient metabolism of xenobiotics.

[Association of the nicotine and cigarette smoke toxicants metabolic (CHRNA3/5, CYP2A6, NQO1) and DNA repair genes (XRCC1, XRCC3, XPC, XPA) with chronic obstructive pulmonary disease].

The contribution of the polymorphic markers of the CHRNA5/A3, CYP2A6, NQO1, XPC, XRCC1, XRCC3, XPD, XPA genes to chronic obstructive pulmonary disease has been assessed. For this purpose, analysis of the gene polymorphisms in case/control groups in Tatar population has been performed. The CHRNA5 (rs16969968) (P = 0.0001, OR = 2.24), CHRNA3 (rs1051730) (P = 0.0001, OR = 2.72) were associated with significantly high risk of chronic obstructive pulmonary disease in recessive model. The disease risk was higher in homozygous carriers of normal allele of CYP2A6 (del) (P = 0.00001, OR = 2.77). Analysis showed an association of the NQO1 (rs1131341), XRCC1 (rs25487), XRCC3 (rs861539), XPC (rs2228001) and XPA (rs1800975) (P = 0.000001, OR = 2.67; P = 0.00001, OR = 0.51; P = 0.0003, OR = 1.76; P = 0.0004, OR = 0.54 and P = 0.007, OR = 0.74) in additive model with chronic obstructive pulmonary disease. We found a significant gene-by-environment interaction of smoking status and XPA (rs1800975) (Pinteract = 0.002); rs16969968, rs1051730 of CHRNA3/5 genes were significantly associated with chronic obstructive pulmonary disease only in smokers. The relationship between the CYP2A6(CYP2A6*4) and smoking pack-years was found (P = 0.0019). The TT genotype of XRCC3 (rs861539) were associated with decreased of lung function parameters: vital capacity % (P = 0.0487), forced vital capacity (%) (P = 0.0032) and forced expiratory volume in 1 s (%) (P = 0.02). The relationship between the XPA (rs1800975) and forced expiratory volume in 1 s (%) (P = 0.0028) was found.

[Analysis of polymorphisms of genes associated with immune response and tissue remodeling in occupational chronic bronchitis].

The involvement of polymorphisms of genes encoding immune response-associated molecules (LTA, TNFA, ILB, ILRN, IL8, IL10, VDBP), matrix metalloproteinases (MMP1, MMP2, MMP3, MMP9, MMP12, ADAM33), and tissue and serum inhibitors of proteases (TIMP2, TIMP3, SERPINA1, SERPINA3) in the predisposition to occupational chronic bronchitis was assessed by PCR-RFLP analysis in groups of patients (n = 122) and healthy employees (n = 166). It was found that occupational chronic bronchitis was associated with polymorphisms of VDBP (P(adj) = 0.00005, OR(adj) = 2.06), MMP1 (P(adj) = 0.00002, OR(adj) = 2.57), ADAM33 (P(adj) = 0.0004, OR(adj) = 2.52), and IL8 (P(adj) = 0.0058, OR(adj) = 2.87). The most significant association was observed for the VDBP polymorphism 1296T>G. The VDBP haplotype GC*1S by the loci 1296T>G and 1307C>A was an informative susceptibility marker (P(adj) = 0.0001, OR(adj) = 2.60, 95% CI (1.62-4.19)). There was also a significant interaction between the VDBP polymorphism 1307C>A and the duration of occupational exposure to hazardous factors (P(interaction) = 0.02). Apparently, the investigated polymorphisms of VDBP, MMP1, ADAM33, and IL8 contribute to the genetic susceptibility to chronic bronchitis induced by dust and toxic agents.

[Polymorphism of DNA repair genes (XRCC1, XRCC3, XPC, XPD, XPA) in ethnic groups from Republic of Bashkortostan].

Genotype and allele-frequency distributions of the excision and homologous recombination of DNA repair genes XRCC1 (rs25487 and rs25489), XRCC3 (rs861539), XPC (rs2228001), XPD (rs13181), XPA (rs1800975) were examined in three ethnic groups from the Republic of Bashkortostan (Russia), Russians, Tatars, and Bashkirs. The data obtained were compared to those for other ethnic groups from Russia and worldwide. Statistically significant differences in the allele-frequency distribution of the XPA gene polymorphic locus rs1800975 (p = 0.03) between the samples of Russians and Tatars were demonstrated. Russians and Bashkirs differed in the allele-frequency distribution of the rs861539 polymorphic locus of the XRCC3 gene (p < < 0.0001), and Tatars and Bashkirs, at the rs861539 locus of the XRCC3 gene (p < 0.0001). In Russians and Tatars from the Republic of Bashkortostan, allele frequencies at the DNA repair gene polymorphic loci examined were consistent with those in the population of Northern and Western Europe, while polymorphic allele-frequency distributions in Bashkirs was similar to that observed in the ethnic group of Gujarati Indians.

[Association of polymorph variants of CYP1A2 and CYP1A1 genes with reproductive and thyroid diseases in female workers of petrochemical industry].

The article presents results obtained in study of relationship between polymorph variants of CYP1A1 and CYP1A2 genes with reproductive and thyroid diseases risk in female workers of petrochemical industry, when compared with reference group females. Variants TD and DD of CYP1A2 gene appeared to be associated with nodes formation in uterus and breast in female workers and reference group females. Following liability markers are obtained: homozygous in rare allele genotype CC of CYP1A1 gene for reproductive and thyroid diseaes (fibrous cystic mastopathy and nodular goitre), heterozygous genotype AG of CYP1A1 gene in uterine myoma and fibrous cystic mastopathy, homozygous in deleted T genotype of CYP1A2 gene in autoimmune thyroiditis. Occupational hazards and long length of service at hazardous industries increase effects of rare alleles of the genes studied.

[Contribution of polymorphic variants of the genes of xenobiotic transformation enzymes, antioxidative defense, and DNA repair to the development of individual predisposition to hepatobiliary and reproductive system diseases in petrochemical workers].

The paper gives the basic results of studying the polymorphic loci of the genes of xenobiotic transformation enzymes, antioxidative defense, and DNA repair in petrochemical workers. Polymerase chain reaction-restriction fragment length polymorphism assay was used to identify markers of the predisposition to the development of toxic hepatitis in men and impaired reproduction in women.

[Role of polymorphic markers of antioxidants (NQO1, GSTP1, GPX1) genes in adaptive response to hazardous work conditions in workers].

The authors presented a comparative study of polymorphous loci Ile105Val and Ala114Val in GSTP1 gene, C609T and C464T in NQO1 gene, Pro197Leu in GPX1 gene of workers engaged into ethylbenzene-styrene (JSC "Salavatnefteorgsintez") and of apparently healthy individuals without occupational exposure to toxic chemicals. The same polymorphous markers were studied in workers differentiated according to health state. Occurrence of genotypes Ile/ Val of GSTP1 gene, Pro/Leu in GPX1 gene in the main group were lower vs. that in the reference one. Occurrence of CC genotype of polymorphous locus of C609T in NQO1 gene in the examinees exceeded that in the reference group. Distribution analysis of haplotypes of NQO1 and GSTP1 revealed high occurrence of *A haplotype of GSTP1 gene and low occurrence of *B haplotype in the main group vs. the reference one. The authors proved that molecular genetic marker of toxic liver affection is a heterozygous genotype of Pro/Leu in GPX1 gene and a combination of II/PL/CC genotypes of polymorphous markers Ile105Val in GSTP1 gene, C609T in NQO1 gene, Pro197Leu in GPX1 gene.

[Use of new DNA diagnostic technologies in occupational medicine].

With the reduced number of workers and the rise of morbidity, including occupational one, the urgent of occupational medicine is to keep the health of able-bodied citizens. Abnormal human gene variants leading to the emergence of functionally reduced gene products (enzymes) underlie susceptibility to this or that illness. The genes of the xenobiotic metabolism system are most studied in this regard. The knowledge of a role of genetic types in the formation of individual susceptibility to environmental hazards has opened up new avenues for studies of predisposition to occupational diseases.

[Association of cytochrome P450 genes polymorphisms (CYP1A1 and CYP1A2) with the development of chronic obstructive pulmonary disease in Bashkortostan].

To assess the role that polymorphisms of cytochrome P450 genes play in genetic predisposition to chronic obstructive pulmonary disease (COPD), the allele and genotype distributions of CYPIA1 (2455 A/G, 3801T/C) and CYP1A2 (-2464T/delT, -163C/A) genes were studied in Tatar and Russian COPD patients and in cases of healthy individuals (Russian, Tatar and Bashkir), residents of Bashkortostan. It was shown that the CYP1A1 and CYP1A2 genes haplotypes frequency distribution patterns do not differed between Tatars and Russians ethnic groups (chi2 = 0.973, df = 3, p = 1.00 and chi2 = 1.546, df = 3, p = 0.92, respectively). Analysis of the the CYP1A1 and CYP1A2 genes haplotypes revealed statistically significant differences in the haplotypes frequency distributions between Bashkirs versus Russians and Tatars (chi2 = 12.328, df= 3,p = 0.008; chi2 = 9.218, df=3, p = 0.034, respectively for CYP1A1 gene and (chi2 = 18.779, df=3, p = 0.0001, chi = 14.326, df=3, p = 0.003, respectively for CYP1A2 gene). The (-2467)delT allele and CYP1A2*1D haplotype of CYPIA2 gene was associated with higher risk of COPD in Tatar ethnic group (OR = 1.83, 95% CI 1.24-2.71, chi2 = 9.48, p = 0.003 and chi2 = 9.733, p = 0.0027, Pcor = 0.008; OR = 3.908, 95% CI 1.56-10.19, respectively). On the other hand the CYP1A2*1A haplotype had protective effect (chi2 = 6.319, p = 0.0127, Pcor = 0.038; OR = 0.6012, 95% CI 0.402-0.898). But at the same time we did not find any differences in the genotypes and haplotypes frequency distributions of the CYP1A2 gene within the patients and healthy groups in Russian ethnic group. We also did not find any association of CYP1A1 gene with COPD in ethnic groups of Bashkortostan.

[Analysis of the cytochrome P450 (CYP1A1) gene polymorphism in the ethnic groups of the Republic of Bashkortostan].

In three ethnic groups from the Republic of Bashkortostan, Russians (N = 451), Tatars (N= 333), and Bashkirs (N= 171), allele, genotype, and haplotype frequency distribution patterns of the CYP1A1 gene single nucleotide polymorphisms, A2455G and T33801C, were investigated. Substantial interethnic differences in the allele frequency distribution patterns of the CYPIA1 polymorphisms A2455G and T3801C (chi2 = 15.61, d.f. = 2, P = 0.0001; and chi2 = 22.10, d.f. = 2, P = 0.0001, respectively) were observed. Pairwise comparison showed that ethnic groups of Tatars and Russians were similar in the A2455G allele frequencies (chi2 = 1.10, d.f. = 1, P = 0.30). However, in case of the T3801C marker, statistically significant differences were revealed (chi2 = 4.56, d.f. = 1, P = 0.032). At the same time, Bashkir ethnic group was found to be statistically significantly different from Russians and Tatars in the CYP1A1 polymorphic allele frequency distribution patterns (chi2 = 15.74, d.f. = 2, P = 0.0001; and chi2 = 7.47, d.f. = 1, P = 0.024, for A2455G, and chi2 = 6.46, d.f. = 1, P = 0.011; and chi2 = 21.36, d.f. = 1, P = 0.0001, for T3801C). Analysis of the CYP1A1 haplotype diversity showed that in terms of the CYP1A1 haplotype frequency distribution patterns, Bashkir ethnic group was statistically significantly different from both Russians (chi2 = 30.07, d.f. = 3, P = 0.0001) and Tatars (chi2 = 11.28, d.f. = 3, P = 0.013). The differences observed were caused by the high frequency of haplotype CYP1A1*2B, which was represented by a combination of rare alleles of the CYP1A1 polymorphisms A2455G and T3801C in Bashkirs (5.81%). On the other hand, the ethnic groups of Russians and Tatars residing in the Republic of Bashkortostan were characterized by similar frequencies of the CYP1A1 haplotypes (chi2 = 6.322, d.f. = 3, P = 0.127). The data obtained could be used in further investigations of the genetic bases of ecology dependant diseases and in the risk groups in the Republic of Bashkortostan.