During the earliest stage of the diseases, IFN-γ-producing T cells (Th1 cells) are found in significantly higher number in the livers, periductular spaces, and peripheral blood of PBC patients while during the late stage of PBC majority of autoreactive CD4+ T cells produce IL-17 and IL-23 (Th17 cells) [2, 3, 12–15]. The gene discussed is IFNG; the disease is primary biliary cholangitis.