MTHFR-Ala222Val and male infertility: a study in Iranian men, an updated meta-analysis and an in silico-analysis

Reprod Biomed Online. 2015 Nov;31(5):668-80. doi: 10.1016/j.rbmo.2015.07.015. Epub 2015 Aug 13.

Abstract

Methylenetetrahydrofolate reductase (MTHFR) functions as a main regulatory enzyme in folate metabolism. The association of MTHFR gene Ala222Val polymorphism with male infertility in an Iranian population was investigated by undertaking a meta-analysis and in-silico approach. A genetic association study included 497 men; 242 had unexplained infertility and 255 were healthy controls. Polymerase chain reaction restriction fragment length polymorphism was used for genotyping MTHFR-Ala222Val. OpenMeta[Analyst] software was used to conduct the analysis; 22 studies were identified by searching PubMed and the currently reported genetic association study. A novel in-silico approach was used to analyse the effects of Ala222Val substitution on the structure of mRNA and protein. Genetic association study revealed a significant association of MTHFR-222Val/Val genotype with oligozoospermia (OR 2.32; 95% CI, 1.12 to 4.78; P = 0.0451) and azoospermia (OR 2.59; 95% CI 1.09 to 6.17; P = 0.0314). Meta-analysis for allelic, dominant and codominant models showed a significant association between Ala222Val polymorphism and the risk of male infertility (P < 0.001). In silico-analysis showed MTHFR-Ala222Val affects enzyme structure and could also change the mRNA properties (P = 0.1641; P < 0.2 is significant). The meta-analysis suggested significant association of MTHFR-Ala222Val with risk of male infertility, especially in Asian populations.

Keywords: Ala222Val polymorphism; Meta-analysis; Methylenetetrahydrofolate reductase gene; idiopathic male infertility; in silico-analysis.

Publication types

  • Meta-Analysis

MeSH terms

  • Adult
  • Asian People / genetics
  • Azoospermia / genetics
  • Case-Control Studies
  • Computer Simulation
  • Genetic Association Studies
  • Genetic Predisposition to Disease*
  • Humans
  • Infertility, Male / genetics*
  • Iran
  • Male
  • Methylenetetrahydrofolate Reductase (NADPH2) / genetics*
  • Oligospermia / genetics
  • Polymorphism, Single Nucleotide*

Substances

  • MTHFR protein, human
  • Methylenetetrahydrofolate Reductase (NADPH2)