ABCB11 and Dubin-Johnson syndrome: Genetic examination identified 11 cases of genetic disorders: Dubin–Johnson syndrome in 2, citrin deficiency in 2, Alagille syndrome in 2, trisomy 21 in 2, bile acid synthesis defects in 1, and two genetic variants of unknown diagnostic significance (e.g., ATP11C and ABCB11) in 2 patients (Table 2).