INTERPHASE ANALYSIS OF X-ANEUPLOIDY BY TH E FLUORESCENCE IN-SITU HYBRIDIZATION IN VARIOUS TISSUES OF HEALTHY-INDIVIDUALS

The frequency of spontaneous X-chromosome hypo- and hyperploidy was st udied in interphase nuclei of cultured and uncultured blood lymphocyte s and oral epithelium of 21 healthy individuals by means of fluorescen ce in situ hybridization of the centromere-specific DNA probe. In wome n, the frequencies of haploid epithelial cells and cultured and uncult ured lymphocytes were 0.84%, 1.59%, and 0.73%, respectively, while the frequency of hyperploid cells was 0.29%, 0.28%, and 0.12% respectivel y. In men, the X-chromosome spontaneous hyperploidy of epithelial cell s, culturesd and uncultured lymphocytes was 0.14%, 0.57%, and 0.11% re spectively. The upper frequency limit of the spontaneous aneuploidy of various cell types was determined for the purpose of being used for t he diagnosis of X-mono- and trisomy mosaicism in women and the disomy in men, In the latter, the frequency of hypoploidy in the cultured lym phocytes was significantly higher than in uncultured lymphocytes. Unde r conditions of intense cell proliferation in FHA-stimulated cultures, more severe disturbances in chromosome segregation are proposed to oc cur than in resting cells.