GSTM1 and beta thalassemia: The mean and range of hemoglobin concentration (Hb g/L), Mean Cellular Volume (MCV fL), Mean Corpuscular Concentration of Hemoglobin (MCH pg) and HbA2 values were collected from 47 SUPT5H heterozygotes reported in the literature (Table S1) and compared to the mean values and ranges for Hb, MCV, MCH and HbA2 levels for the normal [32] and beta-thalassemia carriers [1] as known from the literature.