Seropositive AIH is divided into two subtypes: AIH type 1 (AIH-1), positive for smooth muscle antibodies (SMA) and/or antinuclear antibodies (ANA); and type 2 (AIH-2), positive for liver kidney microsomal antibody type 1 (anti-LKM-1) and/or anti-liver cytosol type 1 (anti-LC1) [1,2,3,4]. The gene discussed is SMN1; the disease is autoimmune hepatitis.