Vitamin D receptor gene BsmI, FokI, ApaI and TaqI polymorphisms and the risk of systemic lupus erythematosus

Recently, several studies have demonstrated the role of vitamin D receptor (VDR) polymorphisms in the development of systemic lupus erythematosus (SLE); however, these results are inconsistent between different cohorts. Therefore, we studied the prevalence of the VDR FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) genotypes and alleles in SLE patients (n = 258) and healthy individuals (n = 545) in a Polish population. We did not observe significant differences for either the VDR FokI, BsmI, ApaI and TaqI genotype and allele frequencies in patients with SLE and healthy individuals. However, the frequency of the VDR F/F and F/f genotypes of FokI was statistically different between patients with renal disease and patients without this symptom OR = 3.228 (1.534–6.792, p = 0.0014), p _corr = 0.0476)]. There was no association of the studied VDR BsmI, ApaI and TaqI polymorphisms with clinical manifestations and laboratory profiles in patients with SLE. Our study indicates that the studied VDR FokI variant might increase the risk of some clinical presentations in patients with SLE.     

Association of CDKN1B gene polymorphisms with susceptibility to breast cancer: a meta-analysis

A number of case–control studies have been conducted to investigate the association of CDKN1B gene polymorphisms with breast cancer. However, these studies reported conflicting results. The aim of our study was to quantitatively summarize the association of CDKN1B gene polymorphisms with breast cancer. Systemic searches of the PubMed, Excerpta Medica Database, and Chinese Biomedical Literature Database databases were performed, with the last report up to Oct 2012. Odds ratios (ORs) with 95 % confidence intervals (CIs) were used to assess the strength of the association. Seven studies including 6,822 cases and 7,186 controls were involved in this meta-analysis, which was performed for two CDKN1B gene polymorphisms (rs2066827 and rs34330). Significant association was found for rs34330 polymorphism (T versus C: OR = 1.10, 95 % CI = 1.03–1.18, P = 0.003; CT + TT versus CC: OR = 1.38, 95 % CI = 0.98–1.93, P = 0.07; TT versus CC + CT: OR = 1.06, 95 % CI = 0.93–1.21, P = 0.38; TT versus CC: OR = 1.23, 95 % CI = 1.04–1.45, P = 0.02; CT versus CC: OR = 1.42, 95 % CI = 0.97–2.09, P = 0.07), but not for rs2066827 polymorphism (G versus T: OR = 0.99, 95 % CI = 0.91–1.08, P = 0.84; TG + GG versus TT: OR = 0.98, 95 % CI = 0.89–1.08, P = 0.69; GG versus TT + TG: OR = 1.04, 95 % CI = 0.83–1.30, P = 0.75; GG versus TT: OR = 1.03, 95 % CI = 0.82–1.30, P = 0.77; TG versus TT: OR = 0.97, 95 % CI = 0.88–1.08, P = 0.58). This meta-analysis suggests that breast cancer may be associated with CDKN1B gene rs34330 polymorphism, but not rs2066827 polymorphism.     

Polymorphic variant at the IL2 region is associated with type 1 diabetes and may affect serum levels of interleukin-2

Polymorphic variants at the interleukin-2 (IL2) locus affect the risk of several autoimmune disorders. Our aim was to evaluate the association of the four IL2 polymorphisms (rs6822844, rs6534349, rs2069762 and rs3136534) with type 1 diabetes (T1D) in the Polish population, and to correlate them with the serum interleukin-2 levels. 543 unrelated T1D patients and 706 healthy control subjects were enrolled. The minor T allele at rs6822844 was significantly less frequent in T1D compared to controls (p = 0.002; OR 0.71; 95 % CI 0.571–0.880). Likewise, the frequency of the TT genotype was decreased among the affected individuals (p = 0.007). In healthy subjects, stratification according to the rs6822844 genotype revealed significant differences in circulating interleukin-2 (p = 0.037) with the highest levels in TT protective genotypes. Three other IL2 polymorphisms did not display significant differences in allele and genotype distribution. In conclusion, the rs6822844 variant is associated with T1D and may play a functional role, or reflect the influence of another causative genetic variant in linkage disequilibrium.     

Association of vitamin D binding protein polymorphism with long-term kidney allograft survival in Hispanic kidney transplant recipients

Polymorphism of genes encoding components of the vitamin D pathway including vitamin D receptor (VDR) and vitamin D binding protein (VDBP), have been widely explored due to the complex role played by vitamin D in renal transplant outcomes. In this study, we investigated whether polymorphisms of genes encoding VDR and VDBP were associated with allograft survival or acute rejection (AR) among a Hispanic kidney transplant population. A total of 502 Hispanic renal allograft recipients at the St. Vincent Medical Center between 2001 and 2010 were genotyped for four different single nucleotide polymorphisms of VDR: FokI C>T (rs2228570), BsmI G>A (rs1544410), ApaI T>G (rs7975232), and TaqI T>C (rs731236). We also performed genotyping for one common polymorphism in the VDBP gene (rs4588). Survival was significantly improved for patients who were homozygous GG for the rs4588 G>T allele in the VDBP gene (GG vs. GT + TT, OR = 0.63, p = 0.02) while GT genotype was associated with a higher risk of graft loss (GT vs. GG + TT, OR = 1.67, p = 0.01). We found no association for polymorphic markers in VDR with allograft survival and AR. The frequency of the haplotype GTCG (in the order of VDR FokI C>T, BsmI G>A, ApaI T>G, and TaqI T>C), was significantly different in the patients with graft rejection compared to the control (p = 0.007) while ACCA haplotype was found to be associated with graft loss (p = 0.02). Hence, the VDBP G>T polymorphism (rs4588) and two haplotypes (GTCG and ACCA) of VDR appear to be associated with renal allograft outcomes among Hispanic allograft recipients.     

Association of the Leptin Gene with Carcass Characteristics in Nellore Cattle

Advances in DNA technology have created biotechnological tools that can be used in animal selection and new strategies for increasing herd productivity and quality. The objective of the present work was to associate the genotypes of leptin gene exon 2 polymorphisms with productive traits in Nellore cattle. Blood was collected from Nellore males and PCR-RFLP reactions were performed with the restriction enzymes ClaI and Kpn2I. The gene frequencies resulting from digestion by ClaI were 0.60 and 0.40 for allele A and T, respectively; the genotypic frequencies were AA = 0.20 and AT = 0.80. The gene frequencies from digestion by Kpn2I were 0.81 for allele C and 0.194 for allele T; the genotypic frequencies were CC = 0.62 and CT = 0.38. The populations in both cases were not in Hardy-Weinberg equilibrium (p > 0.05), and the TT genotype was not found. Significant associations were noted between leptin gene exon 2 polymorphisms and five productive traits in Nellore cattle: carcass fat distribution, the intensity of red muscle coloration, pH, marbling, and post-slaughter fat thickness.     

The CTLA-4 +49 A/G, CT60 A/G and PTPN22 1858 C/T polymorphisms and susceptibility to vitiligo: a meta-analysis

The aim of this study was to explore whether cytotoxic T lymphocyte antigen-4 (CTLA-4) +49 A/G, CT60 A/G, and protein tyrosine phosphatase nonreceptor 22 (PTPN22) 1858 C/T polymorphisms confer susceptibility to vitiligo. A meta-analysis was conducted of the associations between the CTLA-4 +49 A/G, CT60 and PTPN22 1858 C/T polymorphisms and vitiligo using; (1) allele contrast, (2) the recessive model, (3) the dominant model, and (4) the additive model. A total of 14 separate comparisons were considered in our meta-analysis consisting of 3,404 patients with vitiligo and 5,069 controls (nine studies with 1,252 cases and 2,152 controls for the CTLA-4 polymorphisms and five studies with 1,800 cases and 3,269 controls for the PTPN22 polymorphism). Meta-analysis showed no association between vitiligo and the CTLA-4 +49 A/G polymorphism in all study subjects (OR of the G allele = 1.186, 95 % CI = 0.893–1.575, p = 0.240) and in European (OR = 1.016, 95 % CI = 0.873–1.182, p = 0.838). However, meta-analysis of the CTLA-4 CT60 A/G polymorphism showed an association between vitiligo and the CTLA-4 CT60 G allele in all study subjects (OR = 1.267, 95 % CI = 1.110–1.447, p = 4.5 × 10^?5) and in the European group (OR = 1.345, 95 % CI = 1.163–1.556, p = 6.3 × 10^?6). Analysis using the recessive model and homozygote contrast showed the same pattern for the CTLA-4 CT60 G allele. Meta-analysis of the PTPN22 1858 C/T polymorphism showed an association between the PTPN22 T allele and vitiligo in all subjects (OR = 1.507, 95 % CI = 1.320–1.720, p < 1.0 × 10^?8) and in European group (OR = 1.530, 95 % CI = 1.339–1.748, p < 1.0 × 10^?8), but not in Asians (OR = 0.482, 95 % CI = 0.152–1.530, p = 0.216). Analysis using the recessive, dominant model, and homozygote contrast showed the same pattern for the PTPN22 T allele. This meta-analysis demonstrates that the CTLA-4 CT60 A/G polymorphism confers susceptibility to vitiligo in Europeans, but no association was found between the CTLA-4 +49 A/G polymorphism and vitiligo susceptibility. The PTPN22 C1858T polymorphism is associated with vitiligo susceptibility in European population.     

Association of vitamin D receptor gene polymorphisms with the susceptibility to ulcerative colitis in patients from Southeast China

Abstract

The association studies from different ethnic groups showed that vitamin D receptor (VDR) gene polymorphisms might be connected with the susceptibility to ulcerative colitis (UC); however, the conclusions were less consistent. Our study aimed to analyze the associations of UC with common mutations of VDR in Chinese patients. A total of 382 UC patients and 489 healthy controls were recruited. The genotypes of VDR FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) were examined by SNaPshot assays. Haplotype analysis was performed in all study subjects. After Bonferroni correction, the mutant alleles and genotypes of VDR FokI, BsmI, ApaI and TaqI did not statistically differ between UC patients and the controls (all p?>?0.0125). However, the mutant allele C and genotype TC?+?CC of FokI gene were significantly increased in patients with mild and moderate UC compared to those with severe UC (C allele: 54.1% versus 39.3%, OR?=?1.83, 95% CI: 1.21–2.75, p?=?0.004; TC?+?CC genotype: 81.6% versus 57.1%, OR?=?3.32, 95% CI: 1.83–6.06, p?<?0.001, respectively). Haplotype analysis showed that the VDR BsmI, ApaI and TaqI polymorphic loci were in a strong linkage disequilibrium. Furthermore, the frequency of AAC haplotype was statistically lower in UC patients than that in the controls (3.8 versus 5.9%, OR?=?0.63, 95% CI: 0.39–1.01, p?=?0.039). In conclusion, the mutation of FokI gene influenced severity of the disease in UC patients. Moreover, the AAC haplotype formed by the VDR BsmI, ApaI and TaqI gene might engender a reduced risk of UC attack.     

TNFAIP3 gene polymorphisms confer risk for Behcet’s disease in a Chinese Han population

The tumor necrosis factor alpha-inducible protein 3 (TNFAIP3) gene polymorphisms have recently been reported to be associated with the susceptibility to several immune-related diseases. This study was performed to evaluate the potential association of TNFAIP3 polymorphisms with Behcet’s disease (BD) in a Chinese Han population. Five single-nucleotide polymorphisms (SNPs), rs10499194, rs610604, rs7753873, rs5029928, and rs9494885 of TNFAIP3 were genotyped in 722 BD patients and 1,415 healthy controls using a PCR-restriction fragment length polymorphism assay. Allele and genotype frequencies were compared between patients and controls using the χ ² test. The results showed a significantly increased prevalence of the rs9494885 TC genotype and C allele in BD patients compared with controls (Bonferroni corrected p (p _c) = 1.83 × 10^?10, odds ratio (OR) [95 % CI] 2.03 [1.65–2.49]; p _c = 8.35 × 10^?10, OR [95 % CI] 1.81 [1.51–2.18], respectively).The frequency of the TT genotype and T allele of rs9494885 was markedly lower in BD patients than that in controls (p _c = 1.23 × 10^?10, OR [95 % CI] 0.50 [0.40–0.61]; p _c = 8.35 × 10^?10, OR [95 % CI] 0.55 [0.46–0.66], respectively). For rs10499194, a higher frequency of the CC genotype (p _c = 0.015, OR [95 % CI] 1.96 [1.30–2.97]) and C allele (p _c = 0.005, OR [95 % CI] 1.92 [1.28–2.90]), and a lower frequency of the TC genotype (p _c = 0.015, OR [95 % CI] 0.51 [0.34–0.77]) and T allele (p _c = 0.005, OR [95 % CI] 0.52 [0.35–2.97]) were found in BD patients. Concerning rs7753873, a higher frequency of the AC genotype (p _c = 0.015, OR [95 % CI] 1.49 [1.17–1.91]) and C allele (p _c = 0.025, OR [95 % CI] 1.39 [1.11–1.76]), and a lower frequency of the AA genotype (p _c = 0.03, OR [95 % CI] 0.68 [0.53–0.87]) and A allele (p _c = 0.025, OR [95 % CI] 0.72 [0.57–0.91]) were observed in BD patients. This study identified one strong risk SNP rs9494885 and two weak risk SNPs rs10499194 and rs7753873 of TNFAIP3 in Chinese Han BD patients.     

Thymidylate synthase polymorphisms are associated to therapeutic outcome of advanced non-small cell lung cancer patients treated with platinum-based chemotherapy

Thymidylate synthase (TYMS) has three polymorphisms that may modulate thymidylate synthase (TS) expression levels: (1) 28 base pairs (bp) variable number tandem repeat (VNTR) (rs34743033); (2) single nucleotide polymorphism (SNP) C>G at the twelfth nucleotide of the second repeat of 3R allele (rs2853542); and (3) 6 bp sequence deletion (1494del6, rs34489327). This study was conducted to evaluate the influence of TYMS polymorphisms on the survival of Portuguese patients with advanced non-small cell lung cancer (NSCLC) undergoing platinum-based chemotherapy. Our results showed no statistically significant differences between VNTR genotypes; although, considering the SNP C>G, homozygotes 3RG presented a better prognostic at 36 months (p = 0.004) and overall survival (p = 0.003) when compared to 2R3RG patients. Patients with “median/high expression genotypes” demonstrated a better survival at 12 months (p = 0.041) when compared to “low expression genotypes”. Furthermore, 6 bp? carriers (p = 0.006) showed a better survival at 12 months when compared to 6 bp+ homozygotes patients. When analyzing TYMS haplotypes, better survival at 12 months was observed for patients carrying haplotypes with the 6 bp? allele (2R6 bp?; p = 0.026 and 3RG6 bp?; p = 0.045). This is the first report that evaluates the three major TYMS polymorphisms in the therapeutic outcome of NSCLC in Portugal. According to our results, the TYMS polymorphisms may be useful tools to predict which advanced NSCLC patients could benefit more from platinum-based chemotherapy regimens.     

Association between polymorphism of MTHFR c.677C>T and risk of cardiovascular disease in Turkish population: a meta-analysis for 2.780 cases and 3.022 controls

Cardiovascular diseases (CVDs) remain the main cause of morbidity and mortality around the world. A common polymorphism c.677C>T has been identified in the gene coding for methylenetetrahydrofolate reductase (MTHFR), which is involved in the remethylation of homocysteine, and may predispose to CVDs. A meta-analysis was performed to estimate the risk of CVDs associated with MTHFR c.677C>T in Turkish population. Published studies were retrieved from PubMed, Science Citation Index/Expanded, Google Scholar, Turkish Medline, and the Turkish Council of Higher Education Theses Database. For each study, we calculated odds ratios and 95 % confidence intervals (CI), assuming frequency of allele and homozygote comparison, dominant and recessive genetic models. Thirty-one separate studies were included and 2.780 cases/3.022 controls were involved in the current meta-analysis. Significant association was found between c.677C>T polymorphism and risk of CVD when all studies pooled with random-effects model for T versus C (OR 1.33; 95 % CI 1.11–1.59; p = 0.002), TT vs. CC (OR 1.87; 95 % CI 1.35–2.60; p = 3.53E?04), TT+CT vs. CC (OR 1.32; 95 % CI 1.06–1.64; p = 0.014) and TT vs. CT+CC (OR 1.75; 95 % CI 1.29–2.37; p = 6.57E?04). Further analysis indicated the significant association between methylenetetrahydrofolate reductase (MTHFR) TT genotype and groups with venous thrombosis, peripheral arterial thrombosis, acute MI/MI. No publication bias was observed in any comparison model. Our results of meta-analysis suggest that MTHFR c.677C>T polymorphism is associated with the CVDs in Turkish population.     

Lifestyle factors modify obesity risk linked to PPARG2 and FTO variants in an elderly population: a cross-sectional analysis in the SUN Project

Genetic factors may interact with lifestyle factors to modify obesity risk. FTO and PPARG2 are relevant obesogenes. Our aim was to explore the effect of Pro12Ala (rs1801282) of PPARG2 and rs9939609 of FTO on obesity risk and to examine their interaction with lifestyle factors in an elderly population. Subjects (n = 978; aged 69 ± 6) were recruited from the SUN (Seguimiento Universidad de Navarra) Project. DNA was obtained from saliva, and lifestyle and dietary data were collected by validated self-reported questionnaires. Genotyping was assessed by RT-PCR plus allele discrimination. Subjects carrying the Ala allele of PPARG2 gene had a significantly increased obesity risk compared to non-carrier (Pro12Pro) subjects (OR, 1.66; 95  % CI, 1.01–2.74; p = 0.045). Greater obesity risk was also found in inactive or high carbohydrate intake subjects with the Ala12 allele of PPARG2 gene. Interestingly, subjects carrying the Ala allele of the PPARG2 gene and with a high CHO (>246 g/day) intake had an increased obesity risk compared to Pro12Pro subjects (OR, 2.67; 95 % CI, 1.3–5.46; p = 0.007; p for [CHO × PPARG2] interaction = 0.046). Moreover, in subjects with a high CHO intake, the co-presence of the Ala allele of PPARG2 gene and one minor A allele (rs9939609) of FTO gene did increase obesity risk (OR, 3.26; 95 % CI, 1.19–8.89; p = 0.021) when compared to non-carrier (Pro12Pro/TT) subjects. In conclusion, it appears that lifestyle factors may act as effect modifiers for obesity risk linked to Ala12 allele of the PPARG2 gene and the minor A allele of FTO gene in an elderly population.     

Association between the −1438G/A and T102C polymorphisms of 5-HT2A receptor gene and obstructive sleep apnea: a meta-analysis

The serotonin 2A (5-HT2A) receptor has been implicated in obstructive sleep apnea (OSA). Single nucleotide polymorphisms (SNPs) in the 5-HT2A gene have been found in OSA, the most common being ?1438G/A and T102C; however, studies of the association between 5-HT2A SNPs and OSA risk have reported inconsistent findings. A meta-analysis was performed to quantitatively review the association between ?1438G/A and T102C SNPs and OSA. Five studies, including 791 subjects for ?1438G/A genotype and 1,068 subjects for T102C genotype, were selected. Pooled data analysis of the ?1438G/A genotype indicated a significantly increased OSA risk was associated with two variant genotypes (AA vs. AG+GG: OR 3.023, 95 % CI 2.169–4.213, P = 0.506 for heterogeneity; A allele carriers vs. GG: OR 1.938, 95 % CI 0.879–4.274, P = 0.012 for heterogeneity). Stratification analysis by gender supported the association in males, but not females. For the T102C genotype, no significantly increased OSA risk was associated with the two variant genotypes (CC vs. CT+TT: OR 1.065, 95 % CI 0.787–1.442, P = 0.361 for heterogeneity; C allele carriers vs. TT: OR 0.979, 95 % CI 0.737–1.3, P = 0.9 for heterogeneity).In conclusions, meta-analysis indicated that the ?1438G/A, and not T102C, polymorphism of 5-HT2A is a positive risk factor of OSA, especially in males.     

Association of vitamin D receptor FokI and ApaI polymorphisms with lung cancer risk in Tunisian population

Many studies reported that Vitamin D Receptor (VDR) gene polymorphisms might influence the cancer risk due to their antiproliferative, antiangiogenic, and apoptotic effects. The aim of this study was to explore the genetic association of VDR polymorphisms with lung cancer risk in Tunisian population. The genotype and haplotype frequencies of four VDR polymorphisms, FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) were studied using polymerase chain reaction and restriction fragment length polymorphism analysis in 240 patients with lung cancer and 280 healthy controls. The distribution of genotype frequencies differed significantly between lung cancer subjects and controls (FokI P _adj  = 0.002; ApaI P _adj  = 0.013). Haplotype analyses revealed a significant association between G-A-C and A-C-T haplotypes and lung cancer risk (P _corr  = 0.0128, P _corr  = 0.008). When patients were stratified according to gender, age, and smoking, significant associations were detected with FokI and TaqI polymorphisms. We found a lack of association between BsmI, TaqI polymorphisms and lung cancer risk (P > 0.05). Only, the attributable proportion due to interaction and the synergic index for interaction between ApaI polymorphism and smoking were statistically significant (P _adj  = 0.74, 95 % CI = 0.38–1.20) and (P _adj  = 0.63, 95 % CI = 0.05–1.21), respectively. Both the additive interaction measures suggested the existence of a biological interaction between SNP ApaI, but not FokI, and smoking. The multiplicative interaction measure was not statistically significant (P > 0.05). This is the first study in Tunisia, which suggested that VDR FokI and ApaI polymorphisms might be risk factors for lung cancer development.     

Relationships between PON1 Q192R polymorphism and clinical outcome of antiplatelet treatment after percutaneous coronary intervention: a meta-analysis

This meta-analysis was performed to assess the relationships between the PON1 Q192R (rs662 T>C) polymorphism and the clinical outcome of antiplatelet treatment after percutaneous coronary intervention (PCI). A range of electronic databases were searched: Web of Science (1945–2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966–2013), EMBASE (1980–2013), CINAHL (1982–2013) and the Chinese Biomedical Database (CBM) (1982–2013) without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. The crude odds ratio (OR) with their 95 % confidence interval (CI) were calculated. Six clinical cohort studies with a total number of 5,189 patients undergoing PCI for coronary heart disease were included. Our meta-analysis revealed that the PON1 Q192R polymorphism was correlated with an increased risk of major adverse cardiovascular events (MACE) in patients receiving antiplatelet treatment after PCI (C allele vs. T allele: OR = 1.22, 95 % CI 1.04–1.43, P = 0.014; CT+CC vs. TT: OR = 1.38, 95 % CI 1.03–1.86, P = 0.029; CC vs. TT: OR = 1.45, 95 % CI 1.05–1.99, P = 0.024; respectively), especially among Asians. Furthermore, we found significantly positive correlations between the PON1 Q192R polymorphism and the incidence of stent thrombosis in patients receiving antiplatelet treatment after PCI (C allele vs. T allele: OR = 1.42, 95 % CI 1.08–1.87, P = 0.011; CT+CC vs. TT: OR = 1.93, 95 % CI 1.01–3.67, P = 0.046; CC vs. TT: OR = 2.18, 95 % CI 1.09–4.35, P = 0.027; respectively). Our meta-analysis of clinical cohort studies provides evidence that the PON1 Q192R polymorphism may increase the risk of MACE and stent thrombosis in patients receiving antiplatelet treatment after PCI.     

Association Between the Interferon Gamma 874 T/A Polymorphism and the Severity of Valvular Damage in Patients with Rheumatic Heart Disease

Interferon gamma (IFN-γ) is a multifunctional cytokine that plays an important role in modulating almost all phases of the immune response and may be responsible for the increased valvular fibrosis and calcification in the pathogenesis of rheumatic heart disease (RHD). The aim of this study was to investigate the possible relationship between the IFN-γ +874 T/A polymorphism and the severity of valvular damage in the Turkish population. The IFN-γ genotypes were determined in 152 RHD patients and 151 healthy controls by ARMS-PCR. Differences in genotype distribution between patients with RHD and control were evaluated by the χ² test. All statistical analyses were performed with SPSS 15.0 Software program. Frequency of the AA genotype was found to be significantly lower and the TT genotype significantly higher in the RHD group compared to controls (p = 0.002 and p = 0.018, respectively). The TT genotype was found to be significantly higher (26.8% vs. 9.1%, p = 0.009) and the AA genotype significantly lower (29.1% vs. 8.2%, p = 0.001) in the severe valvular disease (SVD) group compared to mild valvular disease group. In the SVD group, 79 patients had mitral balloon valvotomy and/or mitral valve replacement and had significantly higher TT genotype compared to patients with medical follow-up (30.4% vs. 19%, p = 0.001). The data demonstrated that TT genotype is associated with both RHD and the severity of RHD.     

A functional variant of pre-miRNA-196a2 confers risk for Behcet’s disease but not for Vogt–Koyanagi–Harada syndrome or AAU in ankylosing spondylitis

This study aimed to investigate the predisposition of common pre-miRNA SNPs with Behcet’s disease (BD), Vogt–Koyanagi–Harada (VKH) syndrome and acute anterior uveitis (AAU) associated with ankylosing spondylitis (AS). A two-stage association study was carried out in 859 BD, 400 VKH syndrome, 209 AAU⁺AS⁺ patients and 1,685 controls all belonging to a Chinese Han population. Genotyping, the expression of miR-196a and Bach1 (the target gene of miR-196a), cell proliferation, cytokine production were examined by PCR–RFLP, real-time PCR, CCK8 and ELISA. In the first stage study, the results showed significantly increased frequencies of the miR-196a2/rs11614913 TT genotype and T allele in BD patients (adjusted P _c = 0.024, OR = 1.63; adjusted P _c = 5.4 × 10^?3, OR = 1.45, respectively). However, no significant association of the tested SNPs with VKH and AAU⁺AS⁺ patients was observed. The second stage and combined studies confirmed the association of rs11614913 with BD (TT genotype: adjusted P _c = 6×10^?5, OR = 1.53; T allele: adjusted P _c = 8×10^?6, OR = 1.35; CC genotype: adjusted P _c = 0.024, OR = 0.68). A stratified analysis showed an association of the rs11614913 TT genotype and T allele with the arthritis subgroup of BD (P _c = 5.3 × 10^?3, OR = 1.89; P _c = 0.015, OR = 1.56, respectively). Functional experiments showed a decreased miR-196a expression, an increased Bach1 expression and an increased production of IL-1β and MCP-1 in TT cases compared to CC cases (P = 0.023, P = 0.0073, P = 0.012, P = 0.002, respectively). This study shows that a functional variant of miR-196a2 confers risk for BD but not for VKH syndrome or AAU⁺AS⁺ by modulating the miR-196a gene expression and by regulating pro-inflammatory IL-1β and MCP-1 production.     

Case–control association study of polymorphisms in the voltage-gated sodium channel genes SCN1A,SCN2A,SCN3A,SCN1B,and SCN2B and epilepsy

High-frequency action potentials are mediated by voltage-gated sodium channels, composed of one large α subunit and two small β subunits, encoded mainly by SCN1A, SCN2A, SCN3A, SCN1B, and SCN2B genes in the brain. These play a key role in epilepsy, with the most commonly mutated gene in epilepsy being SCN1A. We examined whether polymorphisms in the above genes affect epilepsy risk in 1,529 epilepsy patients and 1,935 controls from four ethnicities or locations: Malay, Indian, and Chinese, all from Malaysia, and Chinese from Hong Kong. Of patients, 19 % were idiopathic, 42 % symptomatic, and 40 % cryptogenic. We genotyped 43 polymorphisms: 27 in Hong Kong, 28 in Malaysia, and 12 in both locations. The strongest association with epilepsy was rs3812718, or SCN1A IVS5N+5G>A: odds ratio (OR) = 0.85 for allele G (p = 0.0009) and 0.73 for genotype GG versus AA (p = 0.003). The OR was between 0.76 and 0.87 for all ethnicities. Meta-analysis confirmed the association (OR = 0.81 and p = 0.002 for G, and OR = 0.67 and p = 0.007 for GG versus AA), which appeared particularly strong for Indians and for febrile seizures. Allele G affects splicing and speeds recovery from inactivation. Since SCN1A is preferentially expressed in inhibitory neurons, G may decrease epilepsy risk. SCN1A rs10188577 displayed OR = 1.20 for allele C (p = 0.003); SCN2A rs12467383 had OR = 1.16 for allele A (p = 0.01), and displayed linkage disequilibrium with rs2082366 (r ² = 0.67), whose genotypes tended toward association with SCN2A brain expression (p = 0.10). SCN1A rs2298771 was associated in Indians (OR = 0.56, p = 0.005) and SCN2B rs602594 with idiopathic epilepsy (OR = 0.62, p = 0.002). Therefore, sodium channel polymorphisms are associated with epilepsy.     

DNA repair genes polymorphism and lung cancer risk with the emphasis to sex differences

Polymorphisms in nucleotide and base excision repair genes are associated with the variability in the risk of developing lung cancer. In the present study, we investigated the polymorphisms of following selected DNA repair genes: XPC (Lys939Gln), XPD (Lys751Gln), hOGG1 (Ser326Cys) and XRCC1 (Arg399Gln), and the risks they present towards the development of lung cancer with the emphasis to gender differences within the Slovak population. We analyzed 761 individuals comprising 382 patients with diagnosed lung cancer and 379 healthy controls. Genotypes were determined by polymerase chain reaction/restriction fragment length polymorphism method. We found out statistically significant increased risk for lung cancer development between genders. Female carrying XPC Gln/Gln, XPC Lys/Gln+Gln/Gln and XRCC1 Arg/Gln, XRCC1 Arg/Gln+Gln/Gln genotypes had significantly increased risk of lung cancer corresponding to OR = 2.06; p = 0.04, OR = 1.66; p = 0.04 and OR = 1.62; p = 0.04, OR = 1.69; p = 0.02 respectively. In total, significantly increased risk of developing lung cancer was found in the following combinations of genotypes: XPD Lys/Gln+XPC Lys/Lys (OR = 1.62; p = 0.04), XRCC1 Gln/Gln+hOGG1 Ser/Ser (OR = 2.14; p = 0.02). After stratification for genders, the following combinations of genotype were found to be significant in male: XPD Lys/Gln+XPC Lys/Lys (OR = 1.87; p = 0.03), XRCC1 Arg/Gln+XPC Lys/Lys (OR = 4.52; p = 0.0007), XRCC1 Arg/Gln+XPC Lys/Gln (OR = 5.44; p < 0.0001). In female, different combinations of the following genotypes were found to be significant: XRCC1 Arg/Gln+hOGG1 Ser/Ser (OR = 1.98; p = 0.04), XRCC1 Gln/Gln+hOGG1 Ser/Ser (OR = 3.75; p = 0.02), XRCC1 Arg/Gln+XPC Lys/Gln (OR = 2.40; p = 0.04), XRCC1 Arg/Gln+XPC Gln/Gln (OR = 3.03; p = 0.04). We found out decreased cancer risk in genotype combinations between female patients and healthy controls: XPD Lys/Lys+XPC Lys/Gln (OR = 0.45; p = 0.02), XPD Lys/Gln+XPC Lys/Lys (OR = 0.32; p = 0.005), XPD Lys/Gln+XPC Lys/Gln (OR = 0.48; p = 0.02). Our results did not show any difference between pooled smokers and non-smokers in observed gene polymorphisms in the association to the lung cancer risk. However, gender stratification indicated the possible effect of heterozygous constitution of hOGG1 gene (Ser/Cys) on lung cancer risk in female non-smokers (OR = 0.20; p = 0.01) and heterozygous constitution of XPC gene (Lys/Gln) in male smokers (OR = 2.70; p = 0.01).     

Intermittent hypoxia maintains glycemia in streptozotocin-induced diabetic rats

Increasing studies have shown protective effects of intermittent hypoxia on brain injury and heart ischemia. However, the effect of intermittent hypoxia on blood glucose metabolism, especially in diabetic conditions, is rarely observed. The aim of this study was to investigate whether intermittent hypoxia influences blood glucose metabolism in type 1 diabetic rats. Streptozotocin-induced diabetic adult rats and age-matched control rats were treated with intermittent hypoxia (at an altitude of 3 km, 4 h per day for 3 weeks) or normoxia as control. Fasting blood glucose, body weight, plasma fructosamine, plasma insulin, homeostasis model assessment of insulin resistance (HOMA-IR), pancreas β-cell mass, and hepatic and soleus glycogen were measured. Compared with diabetic rats before treatment, the level of fasting blood glucose in diabetic rats after normoxic treatment was increased (19.88?±?5.69 mmol/L vs. 14.79?±?5.84 mmol/L, p?<?0.05), while it was not different in diabetic rats after hypoxic treatment (13.14?±?5.77 mmol/L vs. 14.79?±?5.84 mmol/L, p?>?0.05). Meanwhile, fasting blood glucose in diabetic rats after hypoxic treatment was also lower than that in diabetic rats after normoxic treatment (13.14 ± 5.77 mmol/L vs. 19.88 ± 5.69 mmol/L, p<0.05). Plasma fructosamine in diabetic rats receiving intermittent hypoxia was significantly lower than that in diabetic rats receiving normoxia (1.28?±?0.11 vs. 1.39?±?0.11, p?<?0.05), while there were no significant changes in body weight, plasma insulin and β-cell mass. HOMA-IR in diabetic rats after hypoxic treatment was also lower compared with diabetic rats after normoxic treatment (3.48?±?0.48 vs. 3.86?±?0.42, p?<?0.05). Moreover, intermittent hypoxia showed effect on the increase of soleus glycogen but not hepatic glycogen. We conclude that intermittent hypoxia maintains glycemia in streptozotocin-induced diabetic rats and its regulation on muscular glycogenesis may play a role in the underlying mechanism.     

Association of the C825T polymorphism in the GNB3 gene with obesity and metabolic phenotypes in a Taiwanese population

The relationship between obesity and a single nucleotide polymorphism (SNP), rs5443 (C825T), in the guanine nucleotide binding protein beta polypeptide 3 (GNB3) gene is currently inconsistent. In this study, we aimed to reassess whether the GNB3 rs5443 SNP could influence obesity and obesity-related metabolic traits in a Taiwanese population. A total of 983 Taiwanese subjects with general health examinations were genotyped. Based on the criteria defined by the Department of Health in Taiwan, the terms “overweight” and “obesity” are defined as 24 ≦ BMI < 27 and BMI ≧ 27, respectively. Compared to the carrier of the combined CT + TT genotypes of the GNB3 rs5443 polymorphism, triglyceride was significantly higher for the carrier of CC genotype in the complete sample population (128.2 ± 93.2 vs. 114.3 ± 79.1 mg/dl; P = 0.041). In addition, the carriers of CC variant had a higher total cholesterol than those with the combined CT + TT variants (194.5 ± 36.8 vs. 187.9 ± 33.0 mg/dl; P = 0.019) in the complete sample population. In the normal controls, both triglyceride (P = 0.018) and total cholesterol (P = 0.011) were also significantly higher in the CC homozygotes than in the combined CT + TT genotypes. However, the GNB3 rs5443 SNP did not exhibit any significant association with obesity or overweight among the subjects. Our study indicates that the CC genotype of the GNB3 rs5443 SNP may predict higher obesity-related metabolic traits such as triglyceride and total cholesterol in non-obese Taiwanese subjects (but not in obese subjects).