Methylation and the folate pathway are expected to play an important role in the production of healtyh sperm as they are involved in DNA synthesis, repair and methylation. Therefore, Mfady et al (2014) studied the relationship between male infertility and the MTHFR and MTRR polymorphisms. Results showed an association between MTHFR 677TT and male infertility. The presentation of MTHFR A1298C and MTRR A66G genotypes were not different between infertile men and the fertile control group.