Haploinsufficiency of twenty ribosomal subunit genes is known or suspected to cause the inherited bone marrow failure syndrome, Diamond Blackfan anemia (DBA)47, and all of but two of these genes are downregulated in Nan. For example, Rps19, the cause of 25% of DBA cases, is decreased >six-fold. This evidence concerns the gene RPS19 and Blackfan-Diamond anemia.