ObjectiveTo investigate the correlation of X-ray repair cross-complementing gene 1 (XRCC1-Arg399Gln, Arg280His, and Arg194Trp) polymorphisms and susceptibility to gastric cancer. MethodsOne hundred and twenty patients with gastric cancer were included in study group, 120 healthy volunteers were included in control group. The DNA was extracted from peripheral blood. Arg399Gln, Arg280His, and Arg194Trp gene polymorphisms were detected and analyzed using polymerase chain reaction-restriction fragment length polymorphism technique, and the susceptibility between different genotypes and gastric cancer was compared in two groups. ResultsThe age, gender, smoking, drinking, diet, and other common characteristics of exposure factors had no significant differences in two groups (P > 0.05). The mutation locus genotype frequencies of Arg399Gln and Arg280His had no significant differences between two groups (P > 0.05). However, the mutation locus genotype frequencies of Arg/Trp, Trp/Trp, and Arg/Trp+Trp/Trp were higher and the mutation locus genotype frequency of Arg/Arg was lower in the study group as compared with the control group (P < 0.05). ConclusionThe preliminary results from this study shows that XRCC1 Arg399Gln and Arg280His polymorphisms are not correlated with susceptibility to gastric cancer; However, Arg194Trp polymorphism is correlated with susceptibility to gastric cancer.
Objective To summarize the association between CYP1A1 rs4646903 polymorphisms and COPD risk. Methods Systematic literature search was conducted (up to January 2016) in five online databases, ie. PubMed, Embase, China National Knowledge Infrastructure (CNKI), VIP database, and WanFang databases. The strength of association was calculated by odds ratio (OR) and corresponding 95% confidence interval (CI). Results Six case-control studies with 1 050 cases and 1 202 controls were included. This study suggested a significant association between the CYP1A1 rs4646903 polymorphism and COPD risk (CC vs. TT: OR=1.63, 95%CI 1.17-2.27, P=0.004; CC vs. TC+TT: OR=1.62, 95%CI 1.19-2.20, P=0.002). However, there was no significant difference between allele model (C vs. T, OR=1.20, 95%CI 0.95-1.51, P=0.118) and dominant model (CC+TC vs. TT, OR=1.19, 95%CI 0.82-1.72, P=0.366). Conclusions The CYP1A1 rs4646903 polymorphisms might alter the susceptibility of COPD. More well-designed studies with larger sample size are warranted.