DEVELOPMENT OF A SENSITIVE PCR TO DETECT ALLELE LOSS IN A MODEL HEMATOPOIETIC NEOPLASM

Loss or gain of an entire chromosome and interstitial deletions or amp lifications are hallmarks of several hematopoietic neoplasms. These ch romosomal anomalies can be identified by conventional cytogenetic anal ysis of bone marrow aspirates. We Rave developed a PCR-based assay to detect loss of chromosome 5q31 loci, in the model system of myeloid di sorders with the 5q- chromosome (interstitial deletion of 5q), by taki ng advantage of a highly polymorphic dinucleotide repeat within the in terleukin-9 (IL9) gene on 5q31. In a given sample, quantitation of amp lification of individual alleles in a Phosphorlmager allowed the repre sentation of alleles to be expressed as a ratio of the larger to the s maller allele. Comparison of these ratios In paired DNA samples from F icoll buoyant and pelletted fractions provides evidence for allele los s. Results presented here demonstrate that this technique of compariso n of ratios of isotope incorporation could be expanded to investigate any deletion or numerical abnormality in hematopoietic tumors.