EWSR1 and Ewing sarcoma: Anderson et al investigated the genesis of EWSR1-ETS fusions through whole-exome or whole-genome sequencing data from 124 patients with Ewing sarcoma, and their analysis of structural rearrangements revealed that in 52 of 124 (42%) tumors, the EWSR1-ETS fusion arose by chromoplexy, a sudden burst of complex, loop-like rearrangements 47.