ABO and hemoglobinopathy: In a recent study in Greece with patients with hemoglobinopathies the prevalence of alloimmunization up to 2010 was 11.6%, while after 2010, when an extended matching strategy was applied (including ABO, CcDEe, and Kell), the alloimmunization rate decreased to 1.4%, similar to the rate recorded in our study for the general population [21].