[Cytogenetic peculiarity of chromosomal abnormalities in myelodisplastic syndromes in childhood].

Cytogenetic investigation results in bone marrow cells of 70 children and teenagers from 1 to 18 years with myelodysplastic syndromes (MDS) were presented. Between them were 29 girls and 41 boys. According MDS categories were registrated refractory anemia (RA), refractory cytopenia with multilineage dysplasia (RCMD) and refractory anemia with excess blasts (RAEB) (30, 29 and 11 patients, respectively). High spectrum of mosaic clones in bone marrow cells were found: 1) normal and near-tetraploidy 2) abnormal and normal, 3) abnormal, near-tetraploidy and normal, 4) evolution of clonal chromosomal abnormalities and 5) unrelated clones. Normal clone was estimated in 18.6% cases. Karyotype of bone marrow cells in MDS were characterized high frequency of unbalanced (85.7%) and near-tetraploidy clones (45.7%). Between type of structural rearrangements in all categories was dominated deletion - 48.6%. Accordingly categories RA, RCMD, RAEB -50, 41.4 and 45.4%, respectively. More often in structural rearrangements in MDS were involved chromosomes (Chr) 9, 3 and 11, in RA - Chr 9 and 11, in RCMD - Chr 3, 11, 17 and 10, in RAEB - Chr 3 and 9.