Erythroblast membrane-associated protein (ERMAP)

Erythroblast membrane-associated protein (ERMAP) is a single-pass transmembrane glycoprotein of the immunoglobulin superfamily, with a predicted 475-amino-acid sequence including a signal peptide, extracellular immunoglobulin V domain, short transmembrane region, and cytoplasmic B30.2 domain. ERMAP is the carrier of the Scianna blood group antigens (e.g., Sc1, Sc2, Sc3, Rd) and is expressed on the plasma membrane of erythroid cells throughout erythropoiesis. While its precise physiological functions remain incompletely defined, ERMAP likely mediates red cell adhesion and may play roles in immunity via cell–cell or pathogen interaction. The gene is located on chromosome 1p34.2 and regulated by erythropoietic transcription factors. Variant alleles give rise to distinct blood group phenotypes (Scianna and Radin), with clinical relevance for transfusion compatibility and some rare cases of hemolytic transfusion reactions. No currently approved drugs target ERMAP, and individuals lacking functional ERMAP protein are often healthy, suggesting functional redundancy with other membrane proteins.

Other names

Scianna blood group antigenRadin blood group antigenERMAPRDSChERMAPBTN5PRO2801SciannaRadinErythroid membrane-associated protein

None known; not a direct drug target