In euroSIDA study, the survival rate at 12months in HIV patients with mild anemia, (Hb<12g/dl in females and Hb <13g/dl in men), was significantly shorter than in non anemic counter parts (84.1% vs. >96.9%) and it was even much shorter among severely anemic patients (HB<8g/dl) [9]. Here, GSTM1 is linked to anemia (phenotype).