Background: IL-1α produced by Sertoli cells is considered to act as a growth factor for spermatogonia. In this study,
we investigated the association of the C376A polymorphism in IL-1α with male infertility in men referring to the Kashan IVF Center.
Materials and Methods: In this case-control study, 2 ml of blood was collected from 230 fertile and 230 infertile men. After DNA extraction, the C376A variant was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In addition, the molecular effects of the C376A transversion were analysed using bioinformatics tools.
Results: A significant association was observed between the homozygous genotype CC with male infertility [odds ratio
(OR)=1.97, 95% confidence interval (CI)=1.14-3.41, P=0.016)]. Carriers of C (AC+CC) showed a similar risk for
male infertility (OR=1.78, 95% CI=1.06-2.99, P=0.030). Also, allelic analysis showed that the C allele is associated
with male infertility (OR=1.43, 95% CI=1.09-1.88, P=0.011). In sub-group analysis, we found that the AC genotype
is associated with asthenozoospermia (OR=2.38, 95% CI=1.03-5.53, P=0.043). In addition, carriers of C were at
high risk for asthenozoospermia (OR=2.25, 95% CI=1.01-4.10, P=0.047). Also, C allele was significantly associated
with oligozoospermia (OR=1.44, 95% CI=1.01-2.06, P=0.049) and non-obstructive azoospermia (OR=1.67, 95% CI
=1.04-2.68, P=0.034). Finally, in silico analysis showed that the C376A polymorphism could alter splicing especially
in the acceptor site.
Conclusion: This is the preliminary report on the association of IL-1α C376A polymorphism with male infertility in the
Kashan population. This association shows that the IL-1α gene may be a biomarker for male infertility, and therefore
needs additional investigations in future studies to validate this.
Keywords: Genetic Polymorphism, Interleukin-1α, Male Infertility, Spermatogenesi