Association of C677T transition of the human methylenetetrahydrofolate reductase (MTHFR) gene with male infertility
Mohammad Karimian A and Abasalt Hosseinzadeh Colagar A B C
+ Author Affiliations
- Author Affiliations
A Department of Molecular and Cell Biology, Faculty of Basic Sciences, University of Mazandaran, Babolsar 47416-95447, Iran.
B Nano and Biotechnology Research Group, Faculty of Basic Sciences, University of Mazandaran, Babolsar 47416-95447, Iran.
C Corresponding author. Email: acolagar@yahoo.com; ahcolagar@umz.ac.ir
Reproduction, Fertility and Development 28(6) 785-794 https://doi.org/10.1071/RD14186
Submitted: 1 June 2014 Accepted: 24 September 2014 Published: 21 November 2014
Abstract
The human methylenetetrahydrofolate reductase (MTHFR) gene encodes one of the key enzymes in folate metabolism. This gene is located on chromosome 1 (1p36.3), which has 12 exons. The aim of the present study was to investigate the possible association of the two (C677T and A1298C) polymorphisms of this gene with male infertility. In a case-control study, 250 blood samples were collected from IVF centres in Sari and Babol (Iran): 118 samples were from oligospermic men and 132 were from controls. Two single nucleotide polymorphisms of the MTHFR genotype were detected using polymerase chain reaction–restriction fragment length polymorphism. There was no association found between the A1298C variant and male infertility. However, carriers of the 677T allele (CT and TT genotypes) were at a higher risk of infertility than individuals with other genotypes (odds ratio 1.84; 95% confidence interval 1.11–3.04; P = 0.0174). Structural analysis of human MTHFR flavoprotein showed that C677T transition played an important role in the change in affinity of the MTHFR–Flavin adenine dinucleotide binding site. Based on our results, we suggest that C677T transition in MTHFR may increase the risk of male infertility, and detection of the C677T polymorphism biomarker may be helpful in the screening of idiopathic male infertility.
Additional keywords: mutation, oligospermic, polymerase chain reaction–restriction fragment length polymorphism, polymorphism.
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