PAX3 and embryonal rhabdomyosarcoma: While the etiology of ERMS is unclear, ARMS tumors are often characterized by a translocation of chromosomes 2 or 1 and chromosome 13 that creates a novel functional transcription factor fusing the PAX3 or PAX7 DNA binding domain (respectively) to the FOXO1 transactivation domain, with few or no additional tumor-promoting genetic mutations (Galili et al., 1993; Shapiro et al., 1993; Linardic, 2008).