title: Multiple molecular abnormalities in Ph1 chromosome positive acute lymphoblastic leukaemia.
abstract: The Ph1 chromosome is present in 95% of patients with chronic myelogenous leukaemia (CML). The Ph1 chromosome also occurs in 5-25% of children and adults with acute lymphoblastic leukaemia (ALL). This observation raises questions as to whether these diseases are similar or identical. In patients with CML the c-abl and bcr genes are translocated and abnormally expressed. We studied molecular events related to bcr and c-abl in five patients with ALL to determine its relationship to CML. Four had the Ph1 chromosome; the fifth a probable Ph1 chromosome. c-abl and bcr abnormalities identical to CML were detected in four suggesting a common molecular basis. One patient with the Ph1 chromosome and c-abl translocation lacked these molecular changes but had abnormal c-abl gene transcription apparently unrelated to bcr. These data suggest that Ph1 chromosome positive ALL is heterogeneous; in some patients the molecular abnormality is identical to CML; in others c-abl is likewise involved but via a different mechanism.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D004247:DNA / Q000235:genetics; D005260:Female; D006801:Humans; D007945:Leukemia, Lymphoid / Q000235:genetics*; D007951:Leukemia, Myeloid / Q000235:genetics; D008297:Male; D010677:Philadelphia Chromosome; D014158:Transcription, Genetic; D014178:Translocation, Genetic
chemical_list: D004247:DNA