The effectiveness of high–resolution-comparative genomic hybridization in detecting the most common chromosomal abnormalities in pediatric myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a diverse and heterogeneous group of clonal and potentially malignant bone marrow (BM) disorders. The up-to-date used criteria are the ones proposed by the French-American-British (FAB) group in 1982, the World Health Organization (WHO) classification, and a new, recently presented classification: categories cytology cytogenetics (CCC) system or 2003 WHO classification scheme. Comparative genomic hybridization (CGH) is a technique that permits the detection of chromosomal imbalances within a “one step” analysis. In our study, we present 5 cases of MDS and 4 cases of acute myelogenous leukemia (AML). By means of high-resolution CGH (HR–CGH) analysis, we were able to detect DNA copy number alterations in 8 out of 9 samples. The changes were as follows: −7, −Y, del(5)(q33q34), del(11)(q22q24), del(5p), del(9)(q21q31), nullisomy X, and +8. In 5/9 cases the HR-CGH data were highly comparable with conventional cytogenetics and interphase/metaphase fluorescence in situ hybridization findings. Additionally, in 3 BM samples the HR-CGH revealed the presence of changes that had not been detected by conventional cytogenetics: del(5p), del(5)(q33q34), del(9)(q21q31), and nullisomy X. The high effectiveness, specificity, and sensitivity of this method are in concordance with the conventional cytogenetics and FISH findings and the ability to detect new changes.