Complex karyotypes are seen in approximately 20% of patients with myelodysplastic syndromes (MDS) and are associated with a high risk of transformation into acute myeloid leukaemia (AML) and poor prognosis. Acquired uniparental disomy (aUPD, i.e. both copies of a chromosome pair or its part originate from one parent) may contribute to increased genomic instability in bone-marrow cells of patients with MDS.
The pathological potential of aUPD, which arises as a clonal aberration in a proportion of somatic cells, involves tumour suppressor gene and oncogene homozygous mutations. The aim of this study was to evaluate the frequency and implications of uniparental disomy (UPD) in a cohort of 57 patients with MDS and complex karyotype using array comparative genomic hybridization with detection of single nucleotide polymorphisms (aCGH/SNP).