Importantly, both PAX3-FOXO1 RNA and protein could be detected in the samples of normal fetal muscle.     ///    "When constantly expressed, PAX3-FOXO1 interfered with the muscle differentiation process, which presumably contributes to tumorigenesis.. "    ///    "Here, we show that a chimeric RNA, PAX3-FOXO1, identical to that found in alveolar rhabdomyosarcoma, is transiently present in cells undergoing differentiation from pluripotent cells into skeletal muscle. "    ///    "A chimeric fusion RNA, PAX3-FOXO1, associated with alveolar rhabdomyosarcoma, is also present in normal non-cancer cells and tissues. "    ///    "Here, we show that a chimeric RNA, PAX3-FOXO1, identical to that found in alveolar rhabdomyosarcoma, is transiently present in cells undergoing differentiation from pluripotent cells into skeletal muscle."