CIRH1A (cirrhosis, autosomal recessive 1A), also designated cirhin, NAIC or TEX292, is a 686 amino acid protein that, when mutated, causes a severe autosomal recessive intrahepatic cholestasis known as North American Indian childhood cirrhosis (NAIC). NAIC is found in aboriginal children from northwestern Quebec, and is characterized by transient neonatal jaundice which progresses to biliary cirrhosis, portal hypertension and periportal fibrosis during childhood and adolescence. Localizing to nucleolus, CIRH1A contains eleven WD repeats, exists as three alternatively spliced isoforms and is encoded by a gene that maps to human chromosome 16q22.1. Chromosome 16 encodes over 900 genes in approximately 90 million base pairs, makes up nearly 3% of human cellular DNA and is associated with a variety of genetic disorders.