The anemia rate among carriers of αα/–SEA, –α3.7/–α3.7, –α4.2/–α4.2, and –α3.7/–α4.2 ranged from 35.96 to 37.82% (P > 0.05), and no significant differences were observed in Hb levels among those genotypes. This evidence concerns the gene GSTM1 and anemia (phenotype).