This is the first report of the simultaneous occurrence of two BCR/JAK2 fusion transcripts in the same sample and of the longer transcript isoform (BCR exon 1 fused to JAK2 exon 15).     ///    "Notably, both BCR/JAK2 encoded fusion proteins are predicted to juxtapose the coiled-coil dimerization domain of BCR to the catalytically inactive pseudokinase domain (JH2), entirely or partially deprived of the inhibitory region 1 (IR1). "