Acute myelomonocytic leukemia with eosinophilia is commonly associated with pericentric inversions of chromosome 16, involving the core binding factor beta gene (CBFB) on 16q22 and the myosin heavy chain gene (MYH11) on 16p13.
Initial results of bone marrow, chromosome, and flow cytometric analyses were not in accordance with the diagnosis of acute myelomonocytic leukemia with eosinophilia (AML-M4Eo) or AML with a CBFB/MYH11 rearrangement.
Inversion of chromosome 16, inv(16)(p13q22), juxtaposes the core binding factor beta (CBFB) and myosin heavy chain 11 (MYH11) genes, resulting in a myeloid leukemic disease phenotype characterized by increased bone marrow and peripheral blood blasts with myelomonocytic antigen expression and an accompanying eosinophilia.
Moreover, both YAC 854E2, containing the MYH11 gene, and cosmid ZIT133, encompassing the MYH11 breakpoint in inv(16) and t(16;16) of AML-M4 with eosinophilia, demonstrated fluorescent signals on the normal 16, on the der(16), and on the der(12).
Clinical aspects of expression of inversion 16 chromosomal fusion transcript CBFB/MYH11 in acute myelogenous leukemia subtype M1 with abnormal bone marrow eosinophilia.