Abstract: BACKGROUND＆AIM：The research evaluated the micronuclear induction effect by folic acid deficiency in human lymphoblast t(GM13705). The aim of the experiment was to find the optimized folic acid concentration of minimizing genomic damage in the employed cell line. MATERIAL AND METHODS:The experiment employed cytokinesis-block micronucleus assay(CBMN) to evaluate the frequencies of micronucleus induced by folic acid deficiency (6 ～240 nmol/L )in binucleated cell. RESULTS: The frequencies of micronucleated binucleated cell in 6, 60 and 120 nmol/L folic acid groups were significantly increased comparing with 240 nmol/L of folic acid and normal RPMI1640(P<0.05～0.001). But no significant differences were found among the three groups. There was no statistic significance was found between 240 nmol/L and normal RPMI1640 for their frequencies of micronucleated binucleated cell. CONCLUSION: 240 nmol/L of folic acid was able to minimize genetic damage of the tested cell line under the current experimental condition. The genome with BRCA1 mutation may be more sensitive to the stress of folic acid deficiency.

Key words: folic acid, CBMN, binucleated cell, micronucleus