Isolation of molecular hybridisation probes for early myeloid lineage RNAs.

Recombinant plasmid cDNA libraries representing the polyadenylated RNAs in the myeloid cell lines KG1 and ML1 have been constructed. The screening protocol has identified several clones which contain sequences homologous to RNAs expressed at high abundance in one or more of the myeloid cell lines KG1, ML1 and HL60. The relative abundances of RNAs homologous to three recombinants, pML15, pKG21 and pKGA/F5 were measured by an RNA dot hybridisation method in total RNAs isolated from peripheral blood leukocytes from leukaemic patients and normal individuals. High levels of these RNAs were observed mainly in ANLL and acute phase CML samples. The data suggest that these probes have the potential to sub-divide the ANLLs and to extend a molecular classification of the myeloid leukaemias.