Is a Novel Translocation Partner of via t(2;16)(q37;q22) in Acute Myeloid Leukemia.

In a subset of acute myeloid leukemia (AML) cases, the core binding factor beta subunit gene () was rearranged via inv(16)(p13.1q22) or t(16;16)(p13.1;q22), in which the smooth muscle myosin heavy chain 11 gene () was the partner (). Rare variants of rearrangement occurring via non-classic chromosomal aberrations have been reported, such as t(1;16), t(2;16), t(3;16), t(5;16), and t(16;19), but the partners of have not been characterized. We report a case of AML with a complex karyotype, including t(2;16)(q37;q22), in which the protein phosphatase 1 regulatory subunit 7 gene () at chromosome 2q37 was rearranged with (). This abnormality was inconspicuous by conventional karyotype and interphase fluorescence in situ hybridization (FISH), thus leading to an initial interpretation of inv(16)(p13.1q22); however, metaphase FISH showed that the rearrangement involved chromosome 2. Using whole genome and Sanger sequencing, the breakpoints were identified as being located in intron 5 of and intron 7 of . A microhomology of CAG was found in the break and reconnection sites of and , thus supporting the formation of by microhomology-mediated end joining.