A NOVEL 203 KD ABERRANT BCR-ABL PRODUCT IN A GIRL WITH PHILADELPHIA-CHROMOSOME-POSITIVE ACUTE LYMPHOBLASTIC-LEUKEMIA

We report a girl with Ph1-positive ALL with the aberrant BCR-ABL produ ct. In this case, bcr exon 3 jointed not to ordinal abl exon 2 but to exon 3 resulting in the production of a 203 kD BCR-ABL fusion protein with marked tyrosine kinase activity. To our knowledge, this is the fi rst report of an aberrant BCR-ABL product in childhood. This case was characterized with younger age and low leucocyte count at the onset, b ut relapsed early like the typical Ph1-positive ALL, suggesting the di versity in the clinicopathogenesis of Ph1-positive ALL.