Identification of Amplified Genes in a Patient with Acute Myeloid Leukemia and Double Minute Chromosomes

A case of acute myeloid leukemia (M2) with double minute chromosomes and complex karyotypic abnormalities was analyzed cytogenetically and molecularly. Comparative genomic hybridization (CGH) showed that the 8q24 region that contains the MYC oncogene was not amplified. Instead, amplification of chromosomal regions 11q23→qter and 9p11→pter was identified. Southern blot analysis confirmed the CGH findings and showed that the ETS1, FLI1, SRPR, NFRKB, and KCNJ5 genes located at 11q23→24 were amplified, whereas the MLL at 11q23 was not amplified. Additionally, the IFNβ1 and CDKN2A genes at 9p were amplified, but to a lesser degree. This is the first example of a case of acute myeloid leukemia with double minute chromosomes that has not involved amplification of either the MYC or the MLL genes.