Abstract: Objective To study the correlation between phosphodiesterase 5(PDE5) gene polymorphism and penile erectile dysfunction(ED) and its role mechanism. Methods 107 patients with ED and 102 healthy males with physical examination in the hospital between January 2015 and December 2020 were selected as observation group and control group respectively.The basic data were collected in the two groups,and the PDE5 gene polymorphism and levels of serum nitric oxide(NO) and cyclic guanosine monophosphate(cGMP) were detected and compared,and the relationship between each indicator and International Index of Erectile Function 5(IIEF-5) score was analyzed. Results The proportions of T allele and TT genotype at rs3806808 locus in ED group were lower than those in control group(P<0.05).There was a significant difference in the severity of ED among patients with different genotypes at rs3806808 locus of PDE5(P<0.05).The proportion of severe patients in TG and GG groups was lower than that in TT group,while the proportion of mild-to-moderate patients was higher than that in TT group(P<0.05).There was no significant difference in serum NO level in patients with different genotypes at rs3806808 locus of PDE5(P>0.05),and the level of serum cGMP in TG and GG groups was lower than that in TT group while the IIEF-5 score was higher than that in TT group,and the level of serum cGMP in GG group was lower than that in TG group while the IIEF-5 score was higher than that in TG group(P<0.05).Multivariate linear regression analysis showed that serum NO and genotypes at rs3806808 locus of PDE5 were important factors affecting IIEF score in patients with ED(P<0.05).Conclusion Gene polymorphism of PDE5 rs3806808 locus is closely related to the pathogenesis and progression of ED,and its role mechanism may mainly affect the expression of cGMP,but has no obvious relationship with the expression of NO.

Key words: Erectile dysfunction, Phosphodiesterase 5, Gene polymorphism, nitric oxide, cyclic guanosine monophosphate