Comparative analysis of the rates of chromosome damage induced by bleomycin radiomimetic in human trisomic and diploid lymphocytes: in vitro cultures from a mosaic of a Down's syndrome individual.

Lymphocytes with different chromosome numbers (46,XX and 47,XX + 21) in cultures, were obtained from the blood of a mosaic of a Down's syndrome patient. Their distinctive susceptibility to chromosome damage induced by bleomycin radiomimetic was tested and compared with lymphocytes from healthy individuals. The test showed that the presence of an extra chromosome 21 occurred in parallel with the rise of an intrinsic basal rate of chromosome damage in trisomic cells.