ALL- and CML-type BCR:ABL mRNA transcripts in chronic myelogenous leukemia and related disorders

Abstract Using the reverse transcription polymerase chain reaction, we investigated acute lymphoid leukemia (ALL)-type, and chronic myelogenous leukemia (CML)-type BCR/ABL mRNA expression in a total of 66 patients with chronic myeloproliferative disorder (CMPD). Thirty-six of 37 patients with CML were positive for CML-type mRNA. Thirteen of the 25 CML had ALL-type mRNA expression. The patients with ET, PV, MF, and CMML did not have any detectable BCR/ABL expression. The most remarkable finding was that two patients, a Ph 1 -positive CML patient and a patient with a presumptive diagnosis of essential thrombocythemia (ET), showed only ALL-type chimeric mRNA expression.