IFNG and autoimmune hepatitis: Studies have shown that cytochrome P450 IID6 can damage hepatocytes by promoting specific Th1 cells to produce IFN-γ and produce autoantibodies.25 A Chinese study showed that STAT4 polymorphisms were positively associated with AIH-1 in Chinese Han children,71 but a Tunisian study showed that STAT4 polymorphisms were not associated with AIH in the local population, which may be related to a difference in susceptibility genes among different populations.72