Baklouti-Gargouri et al. (2012) explored the possible association of the POLG gene polymorphism with male infertility in Tunisian men. They studied the polymorphic CAG repeat in the nuclear POLG gene in 339 male subjects (216 patients with infertility; 69 azoospermic, 115 oligoasthenoteratospermic and 32 normospermic; and 123 fertile individuals). The heterozygous and the homozygous mutant genotypes 10/≠10 and ≠10/≠10 were significantly more frequent among infertile patients than among fertile controls [11% vs 2% P=1.3×10(-3) and 5% vs 1% P=4.2×10(-7), respectively]. There was also a significant difference between the frequencies of 10/≠10 genotype in azoospermic (4%) and in oligoasthenoteratospermic (16%) infertile patients [P=2.6×10(-2)]. However, the homozygous mutant genotype ≠10/≠10 was seen at similar frequencies in azoospermic, normospermic and oligoasthenospermic men (4%, 3% and 5% respectively).