Association of the CAG repeat polymorphism in mitochondrial polymerase gamma

Polymorphisms in the mitochondrial DNA polymerase gamma (POLG) have been speculated to be associated with male infertility. The main objective of our study was to assess the possible association of CAG repeat polymorphism in POLG1 gene and male 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/ [not equal to] 10 vs 10/10: OR = 2.00 [0.99 - 4.05], p = 0.03; "infertile vs control groups"; 10/[not equal to]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 morbid allele ([not equal to]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. (Afr J Reprod Health 2021; 25[1]: 67-75). Keywords: Infertility, CAG repeat length, Mitochondria, POLG1 gene, sequencing Les polymorphismes de l'ADN polymerase gamma mitochondriale (POLG) ont ete supposes etre associes a l'infertilite masculine. L'objectif principal de notre etude etait d'evaluer l'association possible du polymorphisme de repetition CAG dans le gene POLG1 et l'infertilite masculine dans la population algerienne. L'ADN genomique de 89 hommes steriles et 84 temoins a ete extrait en utilisant la methode de salting-out. Le polymorphisme de repetition CAG a ete analyse par le protocole de sequencage direct automatise. L'analyse statistique a ete realisee par le logiciel Epi-info[R] (v6.0). Une association significative avec l'infertilite masculine a ete trouvee pour le polymorphisme de repetition CAG dans les genotypes heterozygotes (10 / [not equal to] 10 vs 10/10: OR = 2,00 [0,99-4,05], p = 0,03; ; 10 / [not equal to] 10 vs 10/10: OR = 3,75 [1,20-11,96], p = 0,01 ). De plus, les resultats ont montre une association significative entre l'allele morbide ([not equal to] 10) et l'infertilite masculine (2,07 [1.07-4.02], p = 0.01). Nos resultats ont montre que l