The fact that Rps12KO/+ mice exhibit fully-penetrant pancytopenia with a severe bone marrow failure phenotype, in addition to the erythropoiesis defect, raises the possibility that Rps12 might not have been found mutated in DBA patients due to a more severe human phenotype of Rps12 mutation that is not classified as DBA. This evidence concerns the gene RPS12 and Bone marrow hypocellularity.