Polymorphisms of 5,10-Methylenetetrahydrofolate Reductase (MTHFR C677T and A1298C) Gene in Recurrent Spontaneous Abortion / 대한불임학회지

ABSTRACT

OBJECTIVE: Previous studies have suggested that hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR C677T) mutations are associated with increased risk of recurrent spontaneous abortion (RSA). Recently, a second site polymorphism in MTHFR, 1298A-->C, which changes a glutamic acid into an alanine residue, was shown to be associated with a decreased enzyme activity. We tested whether the variant alleles of MTHFR C677T and A1298C are risk factor (biomarker) for RSA. MATERIALS AND METHODS: We analyzed DNA from a case-control study in the Korean DNA was extracted from blood samples of 118 patients with RSA and 123 healthy fertile patients as the controls. MTHFR variant alleles were determined by a PCR-restriction fragment length polymorphism assay. RESULTS: We found no evidence for an association between 677TT genotype and risk of RSA (OR=1.95, 95% CI=0.84~4.50, p=0.12). However, the MTHFR 1298AC (OR=0.36, 95% CI=0.20~ 0.63, p=0.0004) and 1298AC+CC (OR=0.35, 95% CI=0.20~0.61, p=0.0002) genotypes were lower among 118 RSA cases compared with 123 controls, conferring a 2.8-fold decrease in risk of RSA, respectively. Moreover, the combined genotypes of MTHFR 677CC/1298AC (OR=0.30, 95% CI= 0.10~0.88, p=0.029) and 677CT/1298AC (OR=0.77, 95% CI=0.60~0.99, p=0.043) also showed significantly lower risk than those with MTHFR 677CC/1298AA type. CONCLUSION: MTHFR 1298AC, MTHFR 677CC/1298AC and 677CT/1298AC genotypes may represent genetic markers for the protection of RSA at least in Korean women.