Background：

This gene encodes a cell surface glycoprotein that regulates complement-mediated cell lysis， and it is involved in lymphocyte signal transduction. This protein is a potent inhibitor of the complement membrane attack complex， whereby it binds complement C8 and/or C9 during the assembly of this complex， thereby inhibiting the incorporation of multiple copies of C9 into the complex， which is necessary for osmolytic pore formation. This protein also plays a role in signal transduction pathways in the activation of T cells. Mutations in this gene cause CD59 deficiency， a disease resulting in hemolytic anemia and thrombosis， and which causes cerebral infarction. Multiple alternatively spliced transcript variants， which encode the same protein， have been identified for this gene.