Hemoglobinconcentration of the patients ranged between 12 to 17 g/dl, but one male patient had a mild anemia (Hb<12 g/dl).The folate level (5 to 20 ng/ml) and the B12 level (59to 895 pg/ml) were normal in all patients except for twoindividuals, who had folate levels less than 4.9 ng/ml andB12 levels less than 59 ng/ml. This evidence concerns the gene GSTM1 and anemia (phenotype).