Guanglin Cui

Polymorphism of tumor necrosis factor alpha (TNF-alpha) gene promoter, circulating TNF-alpha level, and cardiovascular risk factor for ischemic stroke

BackgroundTumor necrosis factor-α (TNF-α) is one of the most typical pro-inflammatory cytokines with both beneficial and destructive properties for the central nervous system. Increasing evidences have demonstrated the important role of TNF-α in the development of ischemic stroke, but studies examining the possible association with stroke or direct functional effects of polymorphisms in TNF-α have been contradictory.FindingsIn this study, a 2-kb length of the proximal promoter of the TNF-α was screened and four polymorphisms were investigated in the case–control study. Our data confirmed the association between -308G/A variant with stroke in 1,388 stroke patients and 1,027 controls and replicated in an independent population of 961 stroke patients and 821 controls (odds ratio (OR) = 1.34, 95% confidence interval (CI) =1.02 to 1.77 and OR = 1.56, 95% CI = 1.09 to 2.23, respectively). To reconcile the association between polymorphisms and stroke and to give a comprehensive picture of the genetic architecture of this important gene, we performed a meta-analysis of 15 published studies in an Asian population. Our results demonstrated an association between rs1800629 and ischemic stroke (OR = 1.43, 95% CI = 1.21 to 1.69). Another meta-analysis results of 14 studies demonstrated that ischemic stroke patients have higher serum TNF-α level than the control subjects (standardized mean difference (SMD) = 2.33, 95% CI = 1.85 to 2.81). In vitro evaluation of potential interaction between variants of the TNF-α gene (−308G/A, -857C/T, and -1031T/C) demonstrated that these three polymorphisms could interact together to determine the overall activity of the TNF-α gene.ConclusionsThese findings strongly implicate the involvement of TNF-α in the pathogenesis of stroke.

Association of Common Variants of CYP4A11 and CYP4F2 with Stroke in the Han Chinese Population

Objective 20-Hydroxyeicosatetraenoic acid has been shown to play an important role in cerebral vascular function. We hypothesized that polymorphisms in genes encoding 20-Hydroxyeicosatetraenoic acid synthesizing enzymes might confer susceptibility to stroke. Methods and results To test the hypothesis, haplotype tagging single nucleotide polymorphisms and potential functional polymorphisms of CYP4A11 and CYP4F2 genes were genotyped in 558 ischemic stroke patients, 221 hemorrhagic stroke patients and 557 controls. The association analyses were performed at both single nucleotide polymorphism and haplotype levels. We further verified our findings in an independent cohort of 551 ischemic stroke cases and 48 hemorrhagic stroke cases and 694 unaffected controls. We identified CYP4A11 C-296T and CYP4F2 V433M were associated with significantly increased risk of ischemic stroke (CT+TT vs. CC, adjusted odds ratio: 1.50, 95% confidence interval: 1.17–1.93, Pcombined=0.001, Pcorr=0.008; V/M+M/M vs. V/V, odds ratio: 1.38, 95% confidence interval: 1.15–1.65, Pcombined=5.6×10−4, Pcorr=0.005, respectively). Interestingly, the effects of CYP4F2 V433M on ischemic stroke in our study was only evident in male individuals. Conclusion Our results suggest that genetic variation in CYP4A11 and CYP4F2 alters susceptibility to stroke in the Han Chinese population.

Large Scale Meta-Analyses of Fasting Plasma Glucose Raising Variants in GCK, GCKR, MTNR1B and G6PC2 and Their Impacts on Type 2 Diabetes Mellitus Risk

Background The evidence that the variants GCK rs1799884, GCKR rs780094, MTNR1B rs10830963 and G6PC2 rs560887, which are related to fasting plasma glucose levels, increase the risk of type 2 diabetes mellitus (T2DM) is contradictory. We therefore performed a meta-analysis to derive a more precise estimation of the association between these polymorphisms and T2DM. Methods All the publications examining the associations of these variants with risk of T2DM were retrieved from the MEDLINE and EMBASE databases. Using the data from the retrieved articles, we computed summary estimates of the associations of the four variants with T2DM risk. We also examined the studies for heterogeneity, as well as for bias of the publications. Results A total of 113,025 T2DM patients and 199,997 controls from 38 articles were included in the meta-analysis. Overall, the pooled results indicated that GCK (rs1799884), GCKR (rs780094) and MTNR1B (rs10830963) were significantly associated with T2DM susceptibility (OR, 1.04; 95%CI, 1.01–1.08; OR, 1.08; 95%CI, 1.05–1.12 and OR, 1.05; 95%CI, 1.02–1.08, respectively). After stratification by ethnicity, significant associations for the GCK, MTNR1B and G6PC2 variants were detected only in Caucasians (OR, 1.09; 95%CI, 1.02–1.16; OR, 1.10; 95%CI, 1.08–1.13 and OR, 0.97; 95%CI, 0.95–0.99, respectively), but not in Asians (OR, 1.02, 95% CI 0.98–1.05; OR, 1.01; 95%CI, 0.98–1.04 and OR, 1.12; 95%CI, 0.91–1.32, respectively). Conclusions Our meta-analyses demonstrated that GCKR rs780094 variant confers high cross-ethnicity risk for the development of T2DM, while significant associations between GCK, MTNR1B and G6PC2 variants and T2DM risk are limited to Caucasians.

Genetic Variants at Newly Identified Lipid Loci Are Associated with Coronary Heart Disease in a Chinese Han Population

Background Recent genome-wide association studies (GWAS) have mapped several novel loci influencing blood lipid levels in Caucasians. We sought to explore whether the genetic variants at newly identified lipid-associated loci were associated with CHD susceptibility in a Chinese Han population. Methodology/Principal Findings We conducted a two-stage case-control study in a Chinese Han population. The first-stage, consisting of 1,376 CHD cases and 1,376 sex and age- frequency matched controls, examined 5 novel lipid-associated single-nucleotide polymorphisms (SNPs) identified from GWAS among Caucasians in relation to CHD risk in Chinese. We then validated significant SNPs in the second-stage, consisting of 1,269 cases and 2,745 controls. We also tested associations between SNPs within the five novel loci and blood lipid levels in 4,121 controls. We identified two novel SNPs (rs599839 in CELSR2-PSRC1-SORT1 and rs16996148 in NCAN-CILP2) that were significantly associated with reduced CHD risk in Chinese (odds ratios (95% confidence intervals) in the dominant model 0.76 (0.61-0.90; P = 0.001), 0.67 (0.57-0.77; P = 3.4×10−8), respectively). Multiple linear regression analyses using dominant model showed that rs599839 was significantly associated with decreased LDL levels (P = 0.022) and rs16996148 was significantly associated with increased LDL and HDL levels (P = 2.9×10−4 and 0.001, respectively). Conclusions/Significance We identified two novel SNPs (rs599839 and rs16996148) at newly identified lipid-associated loci that were significantly associated with CHD susceptibility in a Chinese Han population.

Polymorphism of HMGA1 is associated with increased risk of type 2 diabetes among Chinese individuals

Aims/hypothesisVariants of the high-mobility group A1 (HMGA1) gene have been shown to be associated with insulin resistance and type 2 diabetes in individuals of European origin. We aimed to determine whether this locus confers significant susceptibility to type 2 diabetes in the Han Chinese population, and thus cross-race susceptibility to type 2 diabetes.MethodsPolymorphisms in HMGA1 were identified by direct sequencing of genomic DNA derived from 192 Chinese participants (96 patients with type 2 diabetes and 96 controls). We then genotyped the common variant IVS5-13insC (c.136-14_136-13insC) in two other independent cohorts, including a total of 2,533 cases and 2,643 ethnically matched controls.ResultsWe confirmed the association of the HMGA1 variant IVS5-13insC (c.136-14_136-13insC) with type 2 diabetes with an OR of 1.34 (95% CI 1.15, 1.56, p = 0.0002 under a dominant model, and 95% CI 1.16, 1.55, p = 0.0002 under an additive model) in the Han Chinese population, corresponding to a population attributable risk fraction of 5.0%.Conclusions/interpretationHMGA1 is an important susceptibility locus that confers a high cross-race risk of the development of type 2 diabetes.

No evidence for association of 12p13 SNPs rs11833579 and rs12425791 within NINJ2 gene with ischemic stroke in Chinese Han population

Recent genome-wide association (GWA) studies have identified two intergenic single nucleotide polymorphisms (SNPs) (rs11833579 and rs12425791) on chromosome 12p13 and within 11 kb of the NINJ2 gene that were significantly associated with stroke in Caucasians. However, the validity of the association has remained controversial. We performed genetic association analyses in three independent cohorts, including total of 3042 cases and 2973 controls. No significant association between these two SNPs and ischemic stroke was detected by meta-analysis after adjustment for cardiovascular risk factors under the additive model. Our data does not support that the common variants on 12p13 are major contributors of ischemic stroke in the Chinese Han population.

Prevalence of common mutations in the CYP17A1 gene in Chinese Han population.

BACKGROUND Congenital adrenal hyperplasia owing to 17α-hydroxylase/17, 20-lyase deficiency is caused by genetic mutations in the CYP17A1 gene. To date, more than 80 different genetic lesions have been described in patients suffering from this disorder. We aimed to estimate the prevalence of CYP17A1 common mutations in Chinese Han population. METHODS We first reported two female patients with 17α-hydroxylase deficiency based on their clinical features and molecular genetics, and then summarized all the mutations of CYP17A1 gene reported around the world. The most common mutations of CYP17A1 among Chinese Han were genotyped in additional 3245 healthy Chinese using Taqman-assays. RESULTS The mutation spectrum in Asian is different from European decent. All healthy controls could detect two CYP17A1 mutations, D487-S488-F489 deletion and TAC329AA, with a prevalence of 1 in 1000 or 2 in 1000, respectively. CONCLUSION Our data demonstrates that these two mutations are major causes of 17α-hydroxylase deficiency in Chinese Han population.

Association between polymorphisms of CYP2J2 and EPHX2 genes and risk of coronary artery disease.

Objective Common polymorphisms within cytochrome P450 2J2 (CYP2J2) and epoxide hydrolase 2 (EPHX2), which are involved in the generation or hydrolysis of epoxyeicosatrienoic acids, may determine susceptibility to the development of cardiovascular disease. To derive a more precise estimation of their relationship, we undertook a case–control study as well as a meta-analysis to assess possible associations of coronary artery disease (CAD) risk with CYP2J2 and EPHX2 genetic variations. Methods Associations among four single nucleotide polymorphisms in CYP2J2 and five in EPHX2 with CAD were examined in a total of 1344 cases and 1267 ethnically and geographically matched controls. To further confirm the effect of two functional variants (G-50T and R287Q) in the development of CAD, we conducted a meta-analysis including seven studies on G-50T polymorphism and six studies on R287Q polymorphism before June 2010. Results No significant association between common polymorphisms within these two genes and CAD was observed in our sample, either using methods of single-locus analysis or haplotype-based analysis. In addition, no association was detected in our meta-analysis between these two functional variants and the risk of developing CAD. Conclusion This case–control study as well as meta-analysis suggested no association between CYP2J2 G-50T and EPHX2 R287Q and the risk of developing CAD.

Association Analysis of Polymorphisms in ROCK2 with Cardiovascular Disease in a Chinese Population

Background Rho-kinase (ROCK) has been shown to play an important role in cardiovascular disease such as coronary artery disease (CAD) and hypertension. Recently, common variants of ROCK2 have been reported to influence blood pressure, but the relationship between common ROCK2 variants and cardiovascular disease has not been extensively studied in the Chinese population. Methods To derive a more precise estimation of their relationship, we screened for the common variants by direct sequencing of all exons of ROCK2, and then we performed genetic association analyses in a CAD case–control study, including a total of 1344 cases and 1267 ethnically and geographically matched controls. Results Unconditional logistic regression showed that no significant association between common variants in the coding region of ROCK2 and CAD was observed in our study (for rs978906, OR = 0.92, 95% CI 0.72–1.20 and P = 0.63; for rs2230774, OR = 0.90, 95% CI 0.70–1.16 and P = 0.47; for rs56304104, OR = 0.97, 95% CI 0.70–1.31 and P = 0.83; respectively). Conclusions The relationship between the ROCK2 polymorphisms and cardiovascular disease risk cannot be entirely discounted and warrants further evaluation in a large population.

Confirmation of genomewide association signals in Chinese Han population reveals risk loci for ischemic stroke.

Background and Purpose— The first genomewide association study of ischemic stroke in whites has identified multiple susceptibility loci. We confirmed this study by examining associations with ischemic stroke in a Chinese Han population. Methods— Twenty-five common variants were genotyped in a relatively large sample size including 1123 subjects with ischemic stroke cases (thrombosis stroke=716, lacunar infarction=407) and 557 normal control subjects. The association analyses were performed at both single nucleotide polymorphism and haplotype levels. False discovery rate q value method was applied for multiple testing corrections. Results— rs11052413, a intergenic single nucleotide polymorphism, was most significantly associated with ischemic stroke independent of traditional cardiovascular risk factors in additive (OR=1.51, 95% CI=1.19 to 1.92, P=7.4×10−4, q=0.018) and dominant models (OR=1.59, 95% CI=1.20 to 2.08, P=9.2×10−4, q=0.023). In addition, both ZNF650 rs10204475 and intergenic single nucleotide polymorphism rs10486776 were associated with ischemic stroke as well as independent of traditional cardiovascular risk factors in dominant models (OR=1.47, 95% CI=1.12 to 1.96, P=0.005, q=0.040 and OR=1.53, 95% CI=1.15 to 2.02, P=0.003, q=0.036, respectively). No significant results were found in stroke subtype analysis after multiple corrections. Conclusion— Our study confirmed previously reported associations between ischemic stroke and rs11052413, rs10486776, and ZNF 650 rs10204475 in a Chinese Han population. The mechanism whereby the genetic variants exert their effects on ischemic stroke remains to be further elucidated.