RHD (gene)

Rh blood group, D antigen also known as Rh polypeptide 1 or cluster of differentiation 240D is a protein that in humans is encoded by the RHD gene.
The RHD gene codes for the RhD erythrocyte membrane protein that is the Rh factor antigen of the Rh [blood group system]. RHD has sequence similarity to RHCE, RhAG, RhBG, and RhCG and these five genes constitute the Rh [blood group system|Rh family]. It was proposed that the erythrocyte Rh complex is a heterotrimer of RhAG, RhD, and RhCE protein subunits. RhAG is a functional ammonia transporter and is required for normal cell surface expression of RhD and RhCE. Patients who lack RhD/RhCE/RhAG on the surface of their erythrocytes have hemolytic anemia. Antibodies to the RhD protein can cause Rh disease.