Homozygous Methylenetetrahydrofolate Reductase C677T Mutation and Male Infertility

Abstract

To the Editor: Methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. The C677T in the gene that encodes MTHFR decreases the activity of the enzyme by 35 percent in persons who are heterozygous for the mutation and by 70 percent in those who are homozygous.1 The prevalence of the homozygous form is estimated to be between 5 percent and 10 percent. One study showed an increase in sperm count and motility after three months of treatment with folinic acid.2 By determining the frequency of the MTHFR C677T mutation, it may be possible to identify patients who have a . . .