Although the mechanism of its effectiveness upon APL remains unclear, the PML-retinoic acid receptor alpha (RARA) chimeric protein produced by t(15;17) is assumed to underlie the sensitivity of APL cells to ATRA.     ///    These data indicated that isoforms of PML-RARA fused transcripts affect neither the clinical features of APL nor the prognosis after treatment with ATRA..     ///    Isoforms of PML-retinoic acid receptor alpha fused transcripts affect neither clinical features of acute promyelocytic leukemia nor prognosis after treatment with all-trans retinoic acid.     ///    There are two major isoforms of PML-RARA transcripts. 