The emergency physician justified the need for urgent transfusion by the presence of signs of poor tolerance (dyspnea, shock, altered mental status, dizziness, fatigue) in 198 (37.4%) cases, the presence of active bleeding in 72 (13.6%) cases, a history of coronary artery disease in 19 (3.6%) cases, the rapid onset of anemia in 14 (2.6%) cases, post chemotherapy aplasia in 13 (2.5%) cases, and a low pre-transfusion Hb level in 7 (1.3%) cases. The gene discussed is GSTM1; the disease is anemia (phenotype).