Association of autoimmune hepatitis with Src homology 2 adaptor protein 3 gene polymorphisms in Japanese patients

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease characterized by an autoimmune reaction to hepatocytes. The Src homology 2 adaptor protein 3 (SH2B3) gene is a member of the SH2B family of adaptor proteins that has been implicated in the integration and regulation of multiple signaling events. SH2B3 is involved in cytokine signaling pathways and serves as a negative mediator of T-cell receptor signaling. Genome-wide association analyses in Caucasians have linked a missense mutation at rs3184504 in SH2B3 with AIH. Accordingly, four selected single-nucleotide polymorphisms (SNPs) in the SH2B3 gene were genotyped in 158 patients with AIH, 327 patients with primary biliary cholangitis, 160 patients with autoimmune pancreatitis, and 325 healthy subjects of Japanese descent. Although the functional rs3184504 was non-polymorphic in 952 subjects, the frequency of the minor rs11065904 T allele was significantly decreased in AIH patients compared with healthy controls (odds ratio (OR)=0.68; corrected P=0.025). Haplotype 2 (rs2238154 A, rs11065904 T and rs739496 G) was associated with resistance to AIH (OR 0.67, P=0.021) as well as to autoimmune pancreatitis (OR=0.70, P=0.035). Our findings suggest that an SNP and haplotype in SH2B3 are associated with AIH.