Association of infertility and methylenetetrahydrofolate reductase genotypes

Infertility is defined as unexplained when all of the tests of a basic infertility evaluation return within normal limits and present in 15% of infertile couples. Some studies indicate that male or female probands contribute to the association of methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) mutations with fertility problems in grown adults. The objective of this study was to analyze the MTHFR s C677T and A1298C genotype distributions in couples with unexplained fertility problems (UFP) and healthy controls. Two common variants C677T and A1298C of the MTHFR gene were screened in infertile couples (n =60 for C677T polymorphism; n=62 for A1298C polymorphism) and controls from Çukurova region of Turkey. The MTHFR genotypes were studied by automated SNP (Single Nucleotide Polymorphism) analysis of Multiplex PCR-amplification/ligation products with ABI Genetic Analyzer. DNA from blood leukocytes was obtained using an Invitrogen Genomic DNA Mini Kit (CA, USA), according to the manufacturer's instructions. Statistically no difference found for frequencies of MTHFR genotypes and allels between the couples with UFP and healthy controls and between males and womens (p>0.05). Frequency of MTHFR 1298 CC genotype for UFP males was lower than control males and this difference was statistically significant (p<0.05). When we compared the folate and homocyctein levels between the couples with UFP and healthy controls and between males and womens, we found statistically significant difference between folate and homocyctein levels of MTHFR 677 heterozygote individuals; homocyctein levels of MTHFR 677 normal individuals; homocyctein levels of MTHFR 1298 heterozygote, normal and homozygote individuals; folate levels of MTHFR 677 heterozygote and normal womans; homocyctein levels of MTHFR 677 normal individuals; folate levels of MTHFR 1298 heterozygote and normal individuals (p<0.05). There are subjects that are not clear on etiopathogenesis of unexplained infertility. In this study, we don't find an association between unexplained infertility and MTHFR C677T polymorphism but we found an association only for MTHFR A1298C polymorphism between males with UFP and controls. There are literatures that showing association between unexplained infertility and two polymorphisms of MTHFR gene. So, there is a necessity for more studies with more case number to clarify this subject. The data presented in this study to support the relation between MTHFR A1298C polymorphisms and fertility problems in grown male adults.