G6PD and congenital dyserythropoietic anemia: They encompass defects of the erythrocyte membrane proteins (hereditary spherocytosis, HS, hereditary elliptocytosis, HE, and hereditary stomatocytosis, Hst) and red cell enzymes metabolism (glucose-6-phosphate dehydrogenase, G6PD, and pyruvate kinase, PK), as well as alterations of erythrocyte precursors, resulting in defective erythropoiesis (congenital dyserythropoietic anemia, CDA) (19).