OBJECTIVETo analyze polymorphisms of genes related to folic acid metabolism among women of child-bearing age from Shanxi.

METHODSBuccal smears were collected from 1070 women of child bearing age with cotton swabs. Sequences of MTHFR C667T and A1298C, MTRR A66G, and SLC19A1 A80G were determined by DNA sequencing. The results were compared with data from other regions of China.

RESULTSFor MTHFR C667T, the wild type homozygote, heterozygous mutants, and homozygous mutants have respectively accounted for 20.5%, 50.3%, and 29.2% of the study group, with the frequency of the mutant T allele being 54.4%. For MTHFR A1298C, these were 68.7%, 29.3%, and 2.0%, with the frequency of mutant C allele being 16.6%. For MTRR A66G, the above frequencies were 51.5%, 41.8%, and 6.7%, with the frequency of the mutant G allele being 27.6%. For SLC19A1 A80G, these were 29.2%, 48.0%, 22.8%, with the frequency of mutation G allele being 46.8%. Compared with other regions of China, women of child-bearing age from Shanxi has shown a significant difference in allelic distribution of MTRR A66G and SLC19A1 A80G (P<0.05).

CONCLUSIONThe polymorphisms of genes related to folic acid metabolism showed significant regional difference. Over half of women from Shanxi have carried high-risk alleles for folic acid insufficiency and should have individualized folic acid supplement.