Blood group Rh(CE) polypeptide (RHCE)

Blood group Rh(CE) polypeptide (RHCE) is a multi-pass transmembrane protein expressed on human erythrocyte membranes and structurally related to ammonia transporter protein families. RHCE encodes both RhC and RhE antigens, critical determinants of the Rh blood group system—the second most clinically significant blood grouping after ABO. Genetic polymorphisms in RHCE underlie extensive antigen variation, with over 50 alleles and many antigenic variants resulting from mutations, gene conversions, and deletions. The RHCE protein is pivotal for maintaining erythrocyte membrane integrity and may play a physiological role in ammonia transport and red blood cell metabolism, influencing intracellular pH and levels of 2,3-bisphosphoglycerate, which are vital for oxygen delivery. RHCE polymorphisms are of major importance in transfusion medicine, as mismatches can provoke immune hemolytic reactions and are the cause of hemolytic disease in newborns when maternal antibodies form against fetal RhCE antigens. RHCE testing and genotyping are routine for patient selection and transfusion protocols, especially in populations where rare variants complicate finding compatible blood.

Other names

Rh polypeptide 1RhPIRh30ARhIXBRhesus C/E antigensCD240CESLC42A4Rh blood group CcEe antigenRh blood group CE antigenRhesus blood group CE proteinRhesus blood group E antigenRhesus blood group Rhce antigenRhC antigenRhE antigenRh protein

None for marketed drugs; antibody-mediated immune reactions drive disease roles (alloimmunization) in transfusion and pregnancy (via anti-RhCE, anti-RhC, anti-RhE antibodies)