Hematological complications Anemia  Grade 3 (Hb < 80 g/L, or transfusion)  Grade 4 (life-threatening consequences)  Grade 5 (death) Thrombocytopenia  Grade 3 (Plt 25–50 x 109)  Grade 4 (Plt < 25 x 109) Neutropenia  Grade 3 (0.5-1 x 109)  Grade 4 (< 0.5 x 109). The gene discussed is GSTM1; the disease is Decreased total neutrophil count.