GSTT1 null genotype contributes to coronary heart disease risk: a meta-analysis.

Many studies have investigated the association between glutathione S-transferase T1 (GSTT1) null genotype and risk of coronary heart disease (CHD), but the impact of GSTT1 null genotype on CHD is still unclear owing to the obvious inconsistence among those studies. This study aims to quantify the strength of association between GSTT1 null genotype and risk of CHD. We searched the PubMed, Embase and Wangfang databases for studies relating the association between GSTT1 null genotype and risk of CHD. We estimated summary odds ratio (OR) with their 95 % confidence interval (95 % CI) to assess the association. 24 case-control studies with 13, 884 CHD cases and 30, 719 controls were included into this meta-analysis. Meta-analysis of total 24 studies showed GSTT1 null genotype was not associated risk of CHD (random-effects OR = 1.17, 95 % CI 0.97-1.42, P = 0.101). After adjustment for heterogeneity, meta-analysis showed GSTT1 null genotype was associated increased risk of CHD both in total population and Caucasians (for total population, fixed-effects OR = 1.12, 95 % CI 1.05-1.21, P = 0.001; for Caucasians, fixed-effects OR = 1.10, 95 % CI 1.02-1.19, P = 0.010). There was no significant association in the other populations. No evidence of publication bias was observed. Meta-analyses of available data suggest the GSTT1 null genotype contributes to increased risk of CHD in Caucasians.