Duan, Honglei, Wang, Xu, Qi, Wenqian, Shi, Jingyi, Han, Liang, Wang, Guohua, Xu, Yanhui, Liu, Jia, and Wang, Jiangbin
Background: To examine the expression characteristics of single nucleotide polymorphisms (SNPs) in the SRD5A2 gene and investigate their potential association with differences in the clinical characteristics between sexes in patients with chronic hepatitis B virus (HBV) infection. Methods: A total of 30 loci in six genes primarily involved in the metabolism and signaling of sex hormones/sex hormone receptors, namely AKR1C2, AKR1C3, HSD17B6, SRD5A1, SRD5A2, and ESR1, were genotyped in 1007 patients from eight counties (cities) in Northeastern China with chronic HBV infection and 1040 healthy controls, and their association with viral replication characteristics and the differences in disease severity between sexes was assessed. Western blotting was conducted to determine the hepatic SRD5A2 protein level and its relationship with the inflammatory activity and fibrosis degree in male and female patients. Results: Two SNP loci in the SRD5A2 gene (rs12470143 and rs7594951) exhibited significant differences in genotype and allele frequencies between sexes, with the proportion of T alleles significantly higher in males than in females. It was found that the incidence and severity of HBV-related liver fibrosis were significantly higher in patients with the T/T genotype in SRD5A2 rs12470143 and rs7594951 than those with the non-T/T genotype. Additionally, serum HBV DNA levels were significantly elevated in T/T patients compared to non-T/T patients. Female patients exhibited significantly lower serum DNA levels compared to male patients. Western blot analysis indicated that greater hepatic SRD5A2 protein levels were associated with higher METAVIR inflammation and fibrosis scores. Furthermore, multivariate analysis showed that the two genetic variants in the SRD5A2 gene (rs12470143 C > T, r7594951 C > T), together with the male sex, age > 50 years old, HBeAg positive status, elevated serum HBsAg load, high serum HBV DNA load, and HBV genotype C, were independent risk factors for HBV-related liver fibrosis. Conclusions: This study demonstrated that two genetic variants in the SRD5A2 gene (rs12470143 C > T, r7594951 C > T) are associated with sex differences in the clinical characteristics of patients with chronic HBV infection. Highlights: There are significant differences in genotype and allele frequencies between male and female patients with chronic hepatitis B virus (HBV) infection at two single nucleotide polymorphism loci (rs12470143 and rs7594951) in the SRD5A2 gene. The proportion of T alleles at the rs12470143 and rs7594951 loci of the SRD5A2 gene are more prevalent in male patients than in female patients. T/T genotypes at the rs12470143 and rs7594951 loci of the SRD5A2 gene exhibit a significant association with a higher prevalence and severity of HBV-related liver fibrosis, as well as higher levels of HBV DNA, in patients with chronic HBV infection. Elevated hepatic SRD5A2 protein levels in patients with chronic HBV infection are significantly associated with more severe liver inflammation and fibrosis. Plain language summary: This study genotyped 30 genetic loci in six genes primarily involved in the metabolism and signaling pathways of sex hormones/sex hormone receptors, including AKR1C2, AKR1C3, HSD17B6, SRD5A1, SRD5A2, and ESR1, in 1007 patients with chronic hepatitis B virus (HBV) infection and 1040 healthy controls. It was found that two single nucleotide polymorphism (SNP) loci in the SRD5A2 gene (rs12470143 and rs7594951) showed significant differences in genotype and allele frequencies between male and female patients. Further, the proportion of the T alleles was significantly higher in males than in females. The study also found that patients with the T/T genotype had a higher incidence and severity of HBV-related liver fibrosis compared to those with other genotypes. Additionally, serum HBV DNA levels were significantly higher in T/T patients compared to non-T/T patients. Female patients had lower serum DNA levels compared to male patients. Further analysis showed that higher levels of the SRD5A2 protein were associated with increased inflammation and fibrosis scores in the liver. Multivariate analysis revealed that the two genetic variants in the SRD5A2 gene, together with male sex, age over 50, HBeAg positive status, elevated serum HBsAg load, high serum HBV DNA load, and HBV genotype C, were independent risk factors for HBV-related liver fibrosis. In summary, this study demonstrated that genetic variations in the SRD5A2 gene are associated with differences in the clinical characteristics of male and female patients with chronic HBV infection. [ABSTRACT FROM AUTHOR]