Model of erythroid production with possible sites of blockage (black bar) in Diamond-Blackfan anemia (DBA) along the pathway from early commitment and proliferation.

Most patients have no or very few recognizable erythroid elements whereas some patients retain a relatively normal number of erythroid precursors with an arrest at the proerythroblast stage. These stages in erythroid development require different molecules, including transcription factors and proteins in the EPO signalling pathway that may be involved in the pathogenesis of DBA. The role for ribosomal protein S19 at the stages of blockage is unclear.