The results indicated that MTHFR C677T, A1298C, and MTRRA66G polymorphisms were significantly associated with male infertility in Asian populations (Dominant model: MTHFR CC + CT vs TT: OR = 0.60, 95% CI (0.53, 0.67), P <.00001; MTHFR AA + AC vs CC: OR = 0.62, 95% CI (0.49, 0.79), P = .0001; MTRR AA + AG vs GG: OR = 0.60, 95% CI (0.45, 0.81), P = .001.
Our results showed that no association exists between the MTRR 66A>G polymorphism and male infertility risk in the total population (GG vs. AA: OR = 1.29, 95% confidence interval [CI] = 1.00-1.66; GA vs. AA: OR = 1.09, 95% CI = 0.92-1.30; dominant model: OR = 1.13, 95% CI = 0.96-1.34; recessive model: OR = 0.83, 95% CI = 0.67-1.03).
MTR A2756G and MTRRA66G were potential candidates in the pathogenesis of male infertility, but more case-control studies were required to avoid false-positive outcomes.
Our findings revealed an association between the single-nucleotide polymorphism A66G in the MTRR gene and male infertility, particularly in oligoasthenozoospermia males, suggesting that this polymorphism is a genetic risk factor for male infertility in Chinese men.