Abstract: Objective The aim of this study was to explore blood interferon-gamma (IFN-γ) gene polymorphism in patients with acute-on-chronic hepatitis B liver failure (HBV-ACLF). Methods 60 patients with HBV-ACLF and 60 healthy persons for physical examination were recruited in our hospital from May 2017 through September 2019, blood genotyping of IFN-γ gene polymorphism sites +874T/A and +2109A/G were performed by Taqman probe quantitative PCR, and the distribution characteristics of genotypes and allele frequencies of the two polymorphism sites were observed. The correlation of the polymorphism sites to the occurrence of ACLF was analyzed by x² test and Hardy-weinberg equilibrium test. Results At IFN-γ+874T/A site, the frequency of TT genotype in patients with HBV-ACLF was 48.3%, significantly lower than 56.7%, while that of AA was 31.7%, significantly higher than 13.3%(P＜0.05) in the healthy persons, and at allele frequencies, the frequency of T allele in patients with HBV-ACLF was 58.3%, significantly lower than 71.7%, while that of A allele was 41.7%, significantly higher than 28.3%(P＜0.05) in the control; at IFN-γ+2109A/G site, the frequency of AA genotype, an Dominant allele homozygote, was 53.3%, significantly lower than 66.7%, while the frequency of GG genotype, an Recessive allele homozygote, was 28.3%, significantly higher than 10.0%(P＜0.05) in the control, and at allele frequency, the frequency of A allele in patients with HBV-ACLF was 62.5%, much lower than 78.3%, while the frequency of G allele was 37.5%, significantly higher than 21.7% (P＜0.05) in healthy persons. Conclusion IFN-γ gene polymorphism is possibly correlated with HBV-ACLF occurrence in patients with hepatitis B, and among which A allele in +874T/A locus and G allele in +2109A/G locus might be the risk gene for HBV-ACLF occurrence. Monitoring IFN-γ gene polymorphism in patients with hepatitis B might be helpful in predicting HBV-ACLF happening.

Key words: Acute-on-chronic liver failure, Hepatitis B, Interferon-γ, Polymorphism of gene