Trisomy 8 and monosomy 7 detected in bone marrow using primed in situ labeling, fluorescence in situ hybridization, and conventional cytogenetic analyses. A study of 54 cases with hematological disorders

Trisomy 8 and monosomy 7 are the two most frequent aneuploidies found in he matological disorders such as myelodysplastic syndrome (MDS) and acute myel oid leukemia (AML). In this study, primed in situ labeling (PRINS), fluores cence in situ hybridization (FISH) and conventional cytogenetic approaches were used to investigate 54 cases of hematopoietic disorders. Of these case s, there were 22 cases of trisomy 8, 2 cases of tetrasomy 8, 14 cases of mo nosomy 7, and 16 cases with two copies of both chromosomes 7 and 8. PRINS w as carried out in interphase nuclei of bone marrow samples using primers th at can specifically detect alpha -satellite DNA sequences of chromosomes 7 and S. In parallel, using the alpha -satellite probes for chromosomes 7 and 8, FISH was performed for all the cases. PRINS and FISH techniques showed similar specificity and sensitivity. In comparison to FISH, PRINS is more a dvantageous since it is a faster, easier, and more cost-effective technique . Additionally, for most of the cases, a higher proportion of aneuploidy wa s detected in metaphases using conventional cytogenetics, as compared to th e one found in interphase nuclei identified with PRINS and FISH techniques. In other words, for these cases, the cells with trisomy 8 or monosomy 7, h ad a distinct proliferative advantage compared to the disomic cell populati on. Therefore, to better quantify the proportion of aneuploid cells in bane marrow, we recommend to investigate the frequency of aneuploidy in nuclei using PRINS, rather than studying only the dividing cells as detected by co nventional cytogenetic techniques. (C) 2001 Elsevier Science me. All rights reserved.