At the gene level, three recurrent fusions (ATXN3-THAP11, AC245595.1-IGK@, and ELMO1-AOAH) were detected in ARMS, and four (COPS4-TBC1D9, PICALM-SYTL2, SMG6-VPS53, and UBE2F-ALS2) in URCS (Table S3), more specifically in patients with an EWSR1-NFATC2 fusion. Here, COPS4 is linked to alveolar rhabdomyosarcoma.