Translocation of bcr-abl gene is characteristically seen in-

In CML BCR-ABL directs the synthesis of a constitutively active BCR-ABL tyrosine kinase , which in CML is usually 210kDa in size . In more than 90% of cases ,BCR - ABL is created by reciprocal translocation ( the so called Philadelphia chromosome) Ref: Robbins. Pathologic basis of disease ;pg 616