MLH1 rs63749795 variant confers increased risk for endometriosis: a genetic association study

Aims The present study aimed to investigate the association between two MutL homolog 1 (MLH1) single-nucleotide polymorphisms (SNPs), rs63749795 and rs63749820, and the risk of endometriosis.Methods This case-control study included 150 patients with endometriosis and 150 matched healthy controls. Genotyping of the MLH1 polymorphisms was performed using the tetra-primer ARMS-PCR methods.Results The frequency of alleles and genotypes for the MLH1 rs63749820 polymorphism and the allelic distribution of MLH1 rs63749795 did not differ significantly between patients with endometriosis and healthy controls. However, the MLH1 rs63749795 polymorphism was found to be significantly associated with increased susceptibility to endometriosis in individuals carrying the CT genotype (OR = 2.42, 95% CI = 1.39–4.23, p = 0.001). Furthermore, analysis of the MLH1 rs63749795 and rs63749820 haplotypes revealed that CC and TT were associated with an increased risk of endometriosis. After applying Bonferroni correction for multiple comparisons (adjusted p < 0.0125), the association for TT remained statistically significant. In contrast, the TC haplotype (OR = 0.50, p = 0.0003) demonstrated a robust protective effect against the disease.Conclusion In the present study, we report for the first time a significant association between the MLH1 rs63749795 polymorphism and susceptibility to endometriosis.