As alloimmunization against blood groups could affect on efficacy and frequency of blood transfusion and antibodies against K & Rh systems were detected in our study, Phenotyping of a newly diagnosed thalassemia patient, specifically Kell and Rh blood group antigens and transfusion of matched blood components was very important in declining the development of RBC alloantibodies and hemolytic transfusion reactions in thalassemia patients. The gene discussed is KEL; the disease is thalassemia.