Known causes of recurrent acute liver failure (RALF) with clinical and biochemical hepatic recovery in the interval include fulminant viral hepatitis, autoimmune hepatitis, disorders of long-chain fatty acid oxidation and the carnitine cycle, dihydrolipoamide dehydrogenase (E3) deficiency (MIM: 246900), and Wolcott-Rallison syndrome (MIM: 226980).3–7 Here we report the identification of homozygous or compound heterozygous mutations in NBAS (neuroblastoma amplified sequence) in 11 individuals with RALF starting in infancy. This evidence concerns the gene NBAS and acute liver failure.