[Studies on chromosome aberrations and dyshemopoiesis in myelodysplastic syndromes]

G banding chromosome analysis of bone marrow cells from 51 cases of MDS, including 34 cases of RA, 4 cases of RAS, and 13 cases of RAEB, was carried out using a short term culture method. The morphological abnormalities of dyspoiesis of 46 patients were studied and correlated with chromosomal changes. The results were as follows: Forty-nine percent of the cases had abnormal karyotypes. The frequency of clonal abnormalities was 36.8 percent in RA and RAS, and 84.6 percent in BAEB. The most important aberrations were +8 in 7, HSR in 2, and "spontaneous" PCC in 6 cases. The latter 2 abnormalities had rarely been reported in the literature. Other findings included 1p+, dup (1) (q25q44), -2, 4p+, -5, 5q-, +8p, -12, 12p+, 12q-, -14, 14q+, t (1; 14), -15, +/-16, +/-17, -18, +19, +20, 20q-, +/-21, +/-22, -X, -Y, +Mar, etc. The study also showed a close relation between chromosome aberrations and dyspoiesis. +8 patients tended to have a high percentage of micronuclei in their erythroblasts, and their dyspoiesis usually involved three cell lineages. Patients with PCC were found to have more polyploid metaphases (in cytogenetic studies) and more multinuclear cells (in bone marrow aspirate slides). The results of our study revealed that the more severe dyspoiesis is, the higher the frequency of chromosome aberrations. We consider chromosome abnormalities to play an important role in the pathogenesis of MDS, with cell fusion being involved as well.