HSPA9 and acute myeloid leukemia: The distal CDR spans chromosome 5q33.1 (148.6–151.1 Mb) and contains 44 genes, including RPS14.[1–3] The proximal CDR spans chromosome 5q31.2 (136.3–138.6 Mb) and contains 30 genes including HSPA9, and is associated with patients that progress from MDS to secondary AML, or have therapy–related MDS and AML.[2–4] Our group, and others, hypothesize that haploinsufficiency of genes on del(5q) contribute to increased apoptosis and peripheral blood cytopenias observed in MDS.