The t(15;17) leads to the formation of two reciprocal fusion genes, PML/RARA on chromosome 15 and RARA/PML on chromosome 17.     ///    "In contrast, recent molecular analysis of APL cases with cytogenetically normal chromosomes 15 and 17 revealed the occurrence of submicroscopic translocations, leading to the formation of non reciprocal fusion genes, either PML/RARA or RARA/PML only. "