<unk>  is a rare inherited disorder affecting the metabolism of bilirubin, a chemical formed from the breakdown of the heme in red blood cells. The disorder results in a form of nonhemolytic jaundice, which results in high levels of unconjugated bilirubin and often leads to brain damage in infants. The disorder is inherited in an autosomal recessive manner. The annual incidence is estimated at 1 in 1 000 000. This syndrome is divided into types I and II, with the latter sometimes called Arias syndrome. These two types, along with Gilbert's syndrome, Dubin–Johnson syndrome, and Rotor syndrome, make up the five known hereditary defects in bilirubin metabolism. Unlike Gilbert's syndrome, only a few causes of<unk>  are known.
Crigler–Najjar syndrome
Gilbert's syndrome  Gilbert's syndrome  1
GRACILE syndrome
Baggio–Yoshinari syndrome
CLOVES syndrome
Hajdu–Cheney syndrome
DeSanto-Shinawi syndrome
Van Gogh syndrome