<unk> <unk>  is a disorder of blood cell production, particularly of the production of erythroblasts, which are the precursors of the red blood cells (RBCs).
Congenital dyserythropoietic anemia type I
Diamond–Blackfan anemia
Congenital hypoplastic anemia
Paroxysmal nocturnal hemoglobinuria
Hereditary spherocytosis
Beta thalassemia
Twin anemia-polycythemia sequence
Hereditary elliptocytosis