This update of the Duffy (FY) blood group system (Meny GM. The Duffy blood group system: a review. Immunohematology 2010;26:51-6) includes additional variants to the Duffy system (International Society of Blood Transfusion system 8; five anti-gens) identified through molecular studies. The most interesting clinical updates, however, include further evaluation of the roles of the Duffy glycoprotein, also known as the atypical chemokine receptor 1, in malaria and hematopoiesis. The transition to understanding the important role of blood group antigens in homeostasis and disease continues.