The influence of polymorphic GSTM1 gene on the increased susceptibility of non-viral hepatic cirrhosis: evidence from observational studies

It is reported that glutathione S-transferase mu (GSTM1) polymorphism is associated with non-viral hepatic cirrhosis (HC). However, some studies showed different views. Therefore, in this paper, a meta-analysis was conducted to get a more comprehensive understanding of GSTM1 polymorphisms in non-viral HC susceptibility. The results showed that GSTM1 null was associated with the increased risk of non-viral HC (OR = 1.337, 95% CI 1.112–1.804, p = 0.005). Subgroup analysis of cirrhosis type revealed that GSTM1 null was a prominent risk factor for alcoholic HC (OR = 1.416, 95% CI 1.112–1.804, p = 0.005). Meanwhile, subgroup analysis of population indicated that the significant differences only existed in Asian population (OR = 1.719, 95% CI 1.212–2.438, p = 0.002). In hospital-based studies, patients with GSTM1 null were more likely in risk of HC (OR = 1.426, 95% CI 1.092–1.863, p = 0.009). Subgroup analysis using genotyping method showed a significant association between GSTM1 null genotype and HC occurrence in the studies employing the multiple PCR genotyping method (OR = 1.559, 95% CI 1.171–2.076, p = 0.002). Based on the results of this analysis, it was concluded that GSTM1 null genotype could increase the susceptibility of non-viral hepatic cirrhosis. In addition, alcohol intake, Asian ethnicity, sample source from hospital and multiple PCR genotyping method may also influence the susceptibility of hepatic cirrhosis.