ABCB11 is a gene that encodes the bile salt export pump (BSEP) protein that is responsible for transporting bile salts from liver cells into the bile ducts for excretion.[33] Multidrug resistance protein 2 (MRP2) is a multidrug resistance protein that is involved in the excretion of bilirubin, and its loss can lead to hyperbilirubinemia and acute liver failure.[34] The relationship between ABCB11 (BSEP) and MRP2 is also reflected in the fact that they both contribute to the transport of bile salts from liver cells into the bile ducts. The gene discussed is ABCB11; the disease is Hyperbilirubinemia.