INTERPHASE CYTOGENETICS ON AGAR CULTURES - A NOVEL-APPROACH TO DETERMINE CHROMOSOMAL-ABERRATIONS IN HEMATOPOIETIC PROGENITOR CELLS

We describe a novel approach to determine the presence of chromosomal aberrations in progenitor cells by in situ hybridization (ISH) on agar cultures. Bone marrow cells of 3 patients suffering from acute myeloi d leukemia (AML) were selected to develop the method. In all 3 cases, numerical aberrations for chromosome 1 and/or 8 were detected by karyo typing and ISH using chromosome-specific centromeric-associated DNA pr obes. These aberrations were used as markers in this study. After in v itro culture of the bone marrow samples in agar, the cells were pretre ated to perform ISH. This approach retains the cytological architectur e of the agar assay, allowing discrimination between chromosomal aberr ations detected in the clonogenic and non-clonogenic cells in culture. With this new technique, the presence of the cytogenetic aberration i n clonogenic cells can be shown at the interphase level.