The mammalian ribosome consists of 4 RNA species and approximately 80 different proteins. The ribosomal proteins are encoded by complex gene families that include at least 1 active intron-containing gene and multiple processed pseudogenes. The RPS14 gene, encoding a ribosomal protein that belongs to the 40S ribosome, and mapping to the commonly deleted region (CDR) of the 5q- syndrome, shows haploinsufficiency in the CD34+ cells of patients with this disorder.