Clonal origin of the Philadelphia translocation in chronic myeloid leukemia demonstrated in somatic cell hybrids using an adenylate kinase-1 polymorphism.

Hybrid cell lines were derived from fusion of rodent cells with leukocytes from a t(9q+; 22q-)-positive chronic myeloid leukemia (CML) patient carrying a chromosome No. 9-linked adenylate kinase-1 (AK1) polymorphism (AK1 1-2). The AK1*2 allele was consistently expressed when 9q+ was present, whereas the AK1*1-coded isozyme was formed when the normal chromosome No. 9 was present. These results provide additional data confirming the clonal origin of the Ph1 translocation in CML.