Chronic myeloid leukemia presenting ALL-type BCR/ABL transcript

Abstract
We investigated the breakpoints of thebcr gene in 46 Ph1-positive CML cases by Southern blot analysis ofbcr rearrangement, and in 17 CML cases by a combination of Southern blot analysis and RT-PCR. By Southern blot, the breakpoint was not identified on M-bcr in three CML cases, of which one case showed the P210-typebcr/abl transcript and two cases showed the ALL-type (P190-type)bcr/abl transcript with or without P210 transcript. Later two cases showed unique hematological profiles such as thrombocytosis, mild myelofibrosis, and relative resistance to alkylating agents. Therefore, the present study suggests that expression of the P190-type transcript may affect clinical and hematological findings in CML.