Fig. 19
From: Clinical significance and mechanisms associated with segmental UPD
Example of multiple sites of mitotic recombination in clonal based selection in cancer. Archival sample of a leukemia case showing acquired regions of expanding homozygosity referred to as copy neutral loss of heterozygosity (CN-LOH). Two mosaic contiguous regions of CN-LOH (arrows) on chromosome 13, consistent with the evolution of two cells lines with mitotic recombination mediated homozygosity initiated at 13q12.11 and 13q12.13. The selection of recombinant cells is driven by conversion of a heterozygous deletion of the MIR15/16 tumor suppressor genes, red rectangle) at13q14.2 to homozygosity (bracket). A similar pattern is seen in the conversion to normal in case 30 (Fig. 12)