Lack of Association between Vitamin D Genetic Polymorphism and Virological Characteristics of Hepatitis B Infection

Abstract

Background: Exploring polymorphisms in vitamin D-related genes (VDR) within the Brazilian population provides a valuable model to contribute to the influence of the host genetic variants on chronic viral hepatitis B (CHB).

Methods: 126 CHB patients were enrolled in the current study and clinical, laboratory, and 25-hydroxyvitamin D [25(OD)D] level data were obtained. Four VDR (rs7975232, rs1544410, rs10735810, rs731236) and 2 vitamin D-binding protein/carrier globulin (GC) polymorphisms (rs4588 and rs7041) were determined using TaqMan assays and nucleotide sequencing. Association studies were conducted among viral infection parameters and the patient's genetic variants.

Results: Most patients were male (52.38%) with a mean age of 44.28 (±14.24) years, self-identified as White (32.54%), and exhibited vitamin D insufficiency status (42.06%). The hepatitis B virus (HBV) genotype A was predominant (50%) and 62.7% of the patients had detectable HBV DNA levels ≤log10 3 IU/mL. A significant association was observed between HBV genotype A with ApaI and FokI single nucleotide polymorphisms. However, no statistical association between VDR polymorphisms and viral load, viral polymerase mutations, or vitamin D status was found. Vitamin D concentration did not correlate to HBV viral load.

Conclusions: Most HBV-infected individuals presented vitamin D insufficiency, and VDR polymorphism was not associated with virological characteristics except with HBV genotype A, demonstrating that some human genetic signatures are related to HBV genotype distribution.