Progressive familial intrahepatic cholestasis represents a group of disorders characterized by defective bile excretion, which causes a multitude of clinical symptoms of variable severity and usually begins in childhood. During the past few decades, a number of gene sequence variants have been shown to be associated with progressive familial intrahepatic cholestasis, and new subtypes continue to be discovered. Sequence variants of the ubiquitinspecific peptidase 53 gene have previously been associated with a novel autosomal recessive form of cholestasis with coincident normal or low γ-glutamyl transferase, with mild phenotypes. Here, we present 2 siblings with novel homozygous sequence variants in the ubiquitin-specific peptidase 53 gene with acute-on-chronic liver failure who underwent liver transplant.