A novel m.6307A>G mutation in the mitochondrial COXI gene in asthenozoospermic infertile men

Mol Reprod Dev. 2013 Jul;80(7):581-7. doi: 10.1002/mrd.22197. Epub 2013 Jun 17.


Infertility affects 10-15% of the population, of which approximately 40% is due to male etiology and consists primarily of low sperm count (oligozoospermia) and/or abnormal sperm motility (asthenozoospermia). Recently, it has been demonstrated that mtDNA substitutions can influence semen quality. In this study, we performed a sequence analysis of the mitochondrial cytochrome oxidase I (COXI) gene in 31 infertile men suffering from asthenozoospermia in comparison to 33 normozoospermic infertile men and 100 fertile men from the Tunisian population. A novel m.6307A>G mutation was found in sperm mitochondrial DNA (mtDNA). This mutation was found in six asthenozoospermic patients, and was absent in normozoospermic and fertile men. We also detected 21 known substitutions previously reported in the Human Mitochondrial Database. The m.6307A>G mutation substitutes a highly conserved asparagine at position 135 to serine. In addition, PolyPhen-2 analysis predicted that this variant is "probably damaging.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Asthenozoospermia / genetics*
  • Base Sequence
  • DNA Mutational Analysis
  • DNA Primers / genetics
  • DNA, Mitochondrial / genetics*
  • Electron Transport Complex IV / chemistry
  • Electron Transport Complex IV / genetics*
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Mutation, Missense / genetics
  • Point Mutation / genetics*
  • Polymorphism, Restriction Fragment Length
  • Protein Conformation
  • Sequence Alignment
  • Tunisia


  • DNA Primers
  • DNA, Mitochondrial
  • Electron Transport Complex IV