Exploring the Impact of STAT4 Non-Synonymous Mutations on Hepatitis B Virus Susceptibility: A Bioinformatics Approach

Abstract

Hepatitis B virus (HBV) remains a significant global health challenge, with an estimated 257 to 350 million individuals living with chronic HBV infection worldwide. Based on the results of genome-wide association studies (GWAS), the STAT4 gene was identified as a viable target for further study into its association with HBV-related liver diseases. The STAT4 signaling pathway is renowned for its critical role in interferon gamma-mediated antiviral response, emphasizing its importance in HBV infection. The present study employed bioinformatics tools to discover potentially damaging nsSNPs and assess the negative consequences of STAT4 gene mutations. The structural prediction, template refinement, and blind protein-ligand docking studies were assessed using various computational approaches to gain a comprehensive understanding of the functional consequences of the STAT4 gene mutations. From a total of 4749 nsSNPs obtained from the NCBI database, 15 missense SNPs were recognized as detrimental by 13 different bioinformatic tools, including SNPnexus>PolyPhen-2>Predict SNP>Mutpred2>PANTHER>SNP& GO>Meta SNP, and SuSpect, among others. Protein stability was assessed using iStable, Mu Pro, CUPSAT, and Dynamut2 databases. The InBio Discover tool was used to study protein interactions, while the GeneMANIA tool was used to investigate gene-gene interactions. Mutation 3D and PTM sites were assessed to confirm SNPs' detrimental nature. To validate nsSNPs such as D668G (rs751205891), C539Y (rs774187563), R508C (rs780829180), T336S (rs770753645), and P331Q (rs1248978329), protein modeling, structural validation, and protein-ligand interaction studies were performed.  These nsSNPs could serve as targets for future STAT4-related disease research. Despite the inherent drawbacks of computational tools, the studies executed in the present work provide valuable perceptions and may serve as a resource for future in vitro and in vivo studies on STAT4's involvement in the immune response to HBV infection.