Association of Vitamin D pathway SNPs and clinical response to interferon in a cohort of HBeAg-negative patients

Aim: Vitamin D modulates biological processes; an influence of vitamin D levels and genetic variants was identified concerning hepatitis B virus infection. We evaluated the role of some SNPs of vitamin D pathway genes in some clinical features of hepatitis B affected patients treated with pegylated interferon. Methods: We investigated SNPs in IL-28B, CYP27B1, CYP27A1, CYP24A1, VDBP and VDR genes, through real-time PCR. Results: VDRApaI SNP was associated to viral load and HBsAg presence at different timings. In logistic regression analyses, VDRApaI AA genotype predicted baseline viral load >6 Log IU/ml (marker of nonresponse), and both virological and biochemical responses. Conclusion: Pharmacogenetic data could help physicians in the prediction of patients with higher probability to achieve a good response.