PAX7 and acute lymphoblastic leukemia: The FOXO1 gene on human chromosome 13q14.11 is fused to either the PAX7 or PAX3 gene as a result of chromosomal translocation in alveolar rhabdomyosarcoma, whereas the FOXO3 gene at 6q21 and FOXO4 gene at Xq13.1 are fused to the MLL gene as a result of chromosomal translocation in secondary leukemia and acute lymphoblastic leukemia (ALL), respectively [17,184].