Association of PON1-L55M Genetic Variation with Idiopathic Male Infertility in an Iranian Population: A Case-Control Study

The risk of male infertility is related to gene polymorphisms that reduce the activity of antioxidant enzymes. Serum paraoxonase 1 (PON1), is an antioxidant calcium-dependent enzyme has been implicated in the pathogenesis of male infertility. This study aimed to explore the relationship between PON1-L55M polymorphism with idiopathic male infertility. In this case–control study Semen samples were collected from 77 healthy men controls and 128 infertile donors. The paraoxonase activity of PON1 enzyme were measured by spectrophotometric methods. Genomic DNA was extracted from sperm and rs854560 (L55M) was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and PCR sequencing. Statistical analysis indicated that significant difference in genotype frequencies of PON1 L55M polymorphism between patients and controls. Our results showed that, the men with a MM genotype (p= 0.021; OR= 0.091, CI=0.012-0.7) had a significant increased risk of idiopathic male infertility than those with a LM genotype (p= 0.013; OR=0.418, CI=0.27-0.855). In addition, PON1 activities in LL genotype were the highest than LM and MM genotype respectively (MM<LM<LL) in both patients and controls. So, the PON1-L55M is more likely to be a risk factor for idiopathic infertility in Iranian men. Based on the findings of this study, PON1 rs854560 (L55M) variation may be related to semen PON1 activity and the risk of idiopathic male infertility in Iranian population. Nevertheless, we suggested that, future studies focused on some factors such as, environmental and epigenetic factors in larger sample size are needed to reach accurate results.