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.
ObjectiveTo study the correlation between CYP1A1 MspI gene polymorphisms and the risk of breast cancer (BC) in Chinese population.MethodsThe case-control studies on the correlation between polymorphisms of CYP1A1 MspI and BC in Chinese population were electronically retrieved in online English database (PubMed and Web of Science) and Chinese database (Chinese National Knowledge Infrastructure, Wanfang, and VIP database) from the date of their establishment to December 31, 2018. Two reviewers completed literature screening according to the inclusion and exclusion criteria, data extraction, and methodological quality assessment of the included studies independently. Reman 5.3 software was used to meta-analysis.ResultsA total 14 case-control studies involving 3 372 cases and 3 510 controls were finally included. The meta-analysis results showed that the CYP1A1 MspI gene polymorphism was associated with BC in Chinese population. Dominant genetic model [OR=1.24, 95%CI was (0.98, 1.58), P=0.08] and heterozygote model [OR=1.11, 95%CI was (0.89, 1.39), P=0.37] had no association with BC in Chinese population, while recessive genetic model [OR=1.66, 95%CI was (1.28, 2.14), P=0.000 1], homozygote model [OR=1.76, 95%CI was (1.26, 2.45), P=0.000 9], and allele contrast genetic model [OR=1.30, 95%CI was (1.08, 1.56), P=0.005] increased the risk of BC in Chinese population.ConclusionIt is demonstrated that in Chinese population, CYP1A1 MspI gene polymorphisms related to the risk of BC, recessive genetic model, homozygote model, and allele contrast genetic model might be the risk factor for BC.