An hsr on chromosome 7 was shown to be an insertion of four copies of the 11q23 MLL gene region in an HIV-related lymphoma

A 45-year-old male with AIDS presented with a cecal diffuse large B-cell lymphoma. Cytogenetic and flourescence in situ hybridization (FISH) studies revealed a complex karyotype with multiple aberrations that included a translocation, t(8;14) involving MYC on chromosome 14. This is specific to B-cell lymphomas. There were also frequently observed secondary changes such as chromosome 1 rearrangement leading to trisomy of 1q and loss of tp53 from the deleted chromosome 17. A unique secondary abnormality was an hsr on chromosome 7, which by FISH and SKY investigations was shown to originate from chromosome 11 involving 4 copies of the MLL gene region.