Hydroxyurea is expected to increase fetal Hemoglobin (Hb) in SCD, likely reducing hemolysis [21].This does not align with the findings of the study of Adekile et al [20] as they did not demonstrate any significant correlation with Hb, fetal Hb, reticulocytes, total bilirubin, or LDH. The gene discussed is GSTM1; the disease is Schnyder corneal dystrophy.