Association of the CAG repeat polymorphism in mitochondrial polymerase gamma (POLG1) with male infertility: a case-control study in an Algerian population

Afr J Reprod Health. 2021 Feb;25(1):67-75. doi: 10.29063/ajrh2021/v25i1.8.

Abstract

Polymorphisms in the have been speculated to be associated with male infertility. The main objective of our study was to CAG repeat polymorphism in POLG1 gene and male mitochondrial DNA polymerase gamma (POLG) assess the possible association of infertility in Algerian population. Genomic DNA from 89 infertile men and 84 controls was extracted using salting-out method. CAG repeat polymorphism was analyzed by the automated direct sequencing protocol. Statistical analysis was performed by Epi-info(r) (v6.0) software. A significant association with male infertility was found for CAG repeat polymorphism in heterozygous genotypes (10/≠10 vs 10/10: OR = 2.00 [0.99 - 4.05], p=0.03; "infertile vs control groups"; 10/≠10 vs 10/10: OR = 3.75[1.20-11.96], p=0.01 "oligoasthenoteratospermic group"). ALso, the results showed a significant association between the mordib allele (≠10) and male infertility (2.07 [01.07 - 04.02], p=0.01). Our results showed that POLG1 CAG repeat polymorphism might be a risk factor for male infertility in Algerian population. Investigations with larger sample sizes and representative population-based cases and matched controls are needed to validate our results.

Keywords: CAG repeat length; Infertility; Mitochondria; POLG1 gene; sequencing.

MeSH terms

  • Adult
  • Algeria
  • Asthenozoospermia
  • Azoospermia
  • Case-Control Studies
  • DNA Polymerase gamma / genetics*
  • Genotype
  • Humans
  • Infertility, Male / genetics*
  • Male
  • Mediator Complex / genetics*
  • Middle Aged
  • Mitochondria
  • Mutation
  • Nucleic Acid Amplification Techniques
  • Oligospermia
  • Sequence Analysis, DNA

Substances

  • MED12 protein, human
  • Mediator Complex
  • DNA Polymerase gamma
  • POLG protein, human