 Chronic myelogenous leukemia (CML) is characterised by the t(9;22)(q34;q11.2) which results in the formation of the BCR/ABL1 fusion gene.     ///    "The study group consisted of all patients diagnosed or suspected to have CML who had interphase FISH analysis at presentation on peripheral blood/bone marrow using a commercially available BCR/ABL1 dual colour, dual fusion probe. "    ///    Fluorescence in situ hybridization patterns of BCR/ABL1 fusion in chronic myelogenous leukemia at diagnosis..     ///    FISH analysis at presentation is used to determine the number of cells with BCR/ABL1 fusion and establish whether the patterns are typical or atypical.     ///    There were 1076 diagnostic samples which were positive for BCR/ABL1 fusion. 