RPL22L1 and Diamond-Blackfan anemia: Approximately half of these ribosomal genes showed a reduction in expression levels within the range 0·5–0·8 in patients with the 5q− syndrome, including RPS14, RPS23, RPL28, RPL31 and RPL22L1. The findings of Gazda et al (2006b) indicate that some ribosomal protein genes are closely co-regulated in humans and that haploinsufficiency for RPS19 results in downregulation of the additional ribosomal protein genes in both haematopoietic progenitor and erythroid cells in DBA patients.