[Relationship between genetic polymorphisms of MTHFR C677T and nonsyndromic cleft lip with or without palate].

OBJECTIVE: To explore the relationship between genetic polymorphisms of MTHFR C677T and nonsyndromic cleft lip with or without palate in Chinese population. METHODS: There were 97 NSCL/P case-parent triads that were selected as case group. At the same period, 104 healthy subjects were selected together with their biological parents as control group. For all the subjects the polymorphism of MTHFR C677T was examined by PCR-RFLP method. RESULTS: There was no statistical difference in genotype and gene frequencies for MTHFR C677T variants among family members between case group and control group in the offspring, fathers and mothers. The odds ratio(OR) between heterozygotes (CT) versus wild homozygotes (CC) were 1.02 (95% CI 0.47-2.21), 0.62 (95% CI 0.29-1.32) and 0.66 (95% CI 0.31-1.40) in the offspring, fathers and mothers, respectively. The OR between mutant homozygotes(TT) versus wild homozygotes (CC) were 1.10 (95% CI 0.44-2.74), 0.95 (95% CI 0.39-2.32) and 0.68 (95% CI 0.28-1.66) in the offspring, fathers and mothers, respectively. The OR between allele (T) versus allele (C) were 1.07 (95% CI 0.72-1.58), 0.98 (95% CI 0.66-1.46) and 0.83 (95% CI 0.56-1.24) in the offspring, fathers and mothers, respectively. T allele could not increase the risk of NSCL/P. For the MTHFR gene C677T variant, transmission disequilibrium test (TDT) analysis yielded no evidence of linkage in the presence of disequilibrium (chi(2) = 1.817, P > 0.05). Results of haplotype-based haplotype relative risk (HHRR) analysis (chi(2) = 1.76, P > 0.05) and family-based association tests (FBAT) (Z = 1.348, P > 0.05) also showed that there was no association between MTHFR C677T variant and the risk of NSCL/P . CONCLUSION: No association between genetic polymorphism of MTHFR C677T and NSCLP was observed. Our findings suggest that the MTHFR gene variations C677T do not contribute to the development of NSCLP in Chinese population.