We found specifically increased class I (HDAC1, HDAC2) and class II (HDAC5, HDAC7, HDAC9, HDAC6, HDAC10) HDAC gene expression in AML patients compared to healthy controls and also confirmed the expression of these genes in various AML cell lines, representative of different AML subtypes. The gene discussed is HDAC2; the disease is acute myeloid leukemia.