The Duffy blood group antigen is a portal of entry for the malarial parasite Plasmodium vivax. Recent work has shown that this protein, also known as DARC, is a promiscuous chemokine receptor. Although there is still no evidence that DARC can signal, its expression in the CNS on neurons (Purkinje cells) and on endothelial cells lining postcapillary venules (the site of leukocyte trafficking) hint at an as yet unknown physiological role. This article reviews the literature, both past and recent, and discusses the biology of this
enigmatic protein.