 The evolution of mutations in the BCR-ABL1 fusion gene transcript renders CML patients resistant to tyrosine kinase inhibitor (TKI) based therapy.     ///    "To detect mutations in the BCR-ABL1 transcript we developed an assay based on the Pacific Biosciences (PacBio) sequencing technology, which allows for single-molecule long-read sequencing of BCR-ABL1 fusion transcript molecules. "    ///    "cDNA was generated from total RNA and a 1,6?kb fragment encompassing the BCR-ABL1 transcript was amplified using long range PCR. "    ///    "Moreover, several transcript isoforms of the BCR-ABL1 transcript were identified in two of the CML patients. "    ///    Clonal distribution of BCR-ABL1 mutations and splice isoforms by single-molecule long-read RNA sequencing..     ///    In summary the PacBio sequencing assay can be applied to detect BCR-ABL1 resistance mutations in both diagnostic and follow-up CML patient samples using a simple protocol applicable to routine diagnosis.     ///    Thus screening for BCR-ABL1 mutations is recommended particularly in patients experiencing poor response to treatment.     ///    "Notably, the assay was determined to be sufficiently sensitive even in patients harboring a low abundance of BCR-ABL1 levels. "    ///    Herein we describe a novel approach for the detection and surveillance of BCR-ABL1 mutations in CML patients.     ///    "Over 10,000 full-length BCR-ABL1 sequences were obtained for all samples studied. "