The relationship between methylenetetrahydrofolate reductase c.677TT genotype and oligozoospermia in infertile male patients living in the Trakya region of Turkey.

Methylenetetrahydrofolate reductase (MTHFR), the key enzyme of the folate metabolic pathway, has been reported to be five times more active in the testicles compared to other organs in adult mice. The aim of this study was to investigate the relationship between MTHFR c.677C>T and c.1298A>C polymorphisms and infertility in nonobstructive azoospermic and oligozoospermic male patients living in the Trakya region of Turkey. The study population included 75 nonobstructive azoospermic and 62 oligozoospermic, nonconsanguineous patients who were referred to the Department of Medical Genetics of Trakya University between 01.03.2012 and 01.06.2013 due to infertility and who had been diagnosed based on clinical examinations and spermiograms. All of the patients had a normal karyotype without a Y chromosome microdeletion. Melting curve analysis with labelled probes and primers that were designed by the manufacturers and the real-time polymerase chain reaction method were used. The MTHFR c.677TT genotype frequency in the oligozoospermic infertile male patient group was greater than that of the fertile control group [odds ratio (OR) = 2.675 (95% CI: 0.979-7.305), (P < 0.048)]. The MTHFR c.677TT genotype may be a genetic risk factor for oligozoospermic infertile male patients who live in the Trakya region of Turkey.