Investigation of mitochodrial DNA in oligoasthenospermic infertile patients with and without varicocele

2. ABSTRACTInvestigation of Mitochodrial DNA in Oligoasthenospermic InfertilePatients with and without VaricoceleInfertility is the inability of achieving pregnancy of couples having regularsexual activity without contraception in one year. Fifteen percent of the couplesseek medical treatment for infertility. Male causes in infertility are found nearly50% of the couples. The most common cause of male infertility is varicocele.Varicocele causes a decreased number of spermatozoa (oligozoospermia),decreased motility (asthenozoospermia) and many abnormal forms onmorphological examination (teratozoospermia) in semen analysis. It is generallyaccepted that mitochondria play a key role in the energy metabolism as theycontain the enzymes of the oxidative phosphorylation system (OXPHOS), whichprovides the energetic needs of the cells. Mitochondrial DNA (mtDNA) codesonly some few subunits of the OXPHOS enzymatic complexes. Mutations ofmitochondrial or nuclear DNA coding the subunits of mitochondrial machineryhave been implicated in a variety of human diseases especially in the organs witha high demand for respiratory energy, like skeletal muscle, heart, kidney, brain,liver, and germinal tissue. Kao et al, demonstrated that mtDNA deletion wasassociated with diminished fertility and motility of human sperm and that thehighest frequency of occurrence of the deletion coincided with reduced spermmotility.In the present study we aimed to compare the mitochondrial deletion in thecontrol fertil group (n=20) with the oligoasthenospermic infertil patients withvaricocele (n=20) and without varicocele (n=20). After comparison of 7345bp and7599bp deletions in the oligoasthenospermia group with varicocele and the10control group, a significant difference was revealed (p=0,009 and p=0,019). Asignificant difference was shown after comparison of 7345bp and 7599bp deletionbetween the oligoasthenospermia group without varicocele and the control group(p=0,011 and p=0,009). The comparison of 7345bp and 7599bp deletions betweenthe oligoasthenospermia groups with and without varicocele showed a significantdifference (p=0,02 and p=0,042).In our study it was shown that mtDNA deletions are more commonespecially in the oligoasthenospermia group without varicocele. And aftercomparing the infertile oligoasthenospermia group with the control, it was shownthat deletions were more commonly detected in the infertile varicocele group thanthe control group.Key Words: Infertility, mtDNA deletions, Varicocele.11