title: [Variability in the expression of the fragile site of the (fra)X chromosome in 2 consecutive cell cycles].
abstract: The number and morphology of X chromosomes were analysed in tetraploid cells induced with colcemid in cultured blood lymphocytes obtained from a patient with fra(X) syndrome of mental retardation. In contrast to diploid cells containing fra(X) chromosome in 22.7% of cells, the marker X was found in 51.6% of tetraploids, each cell containing only one fragile X out of the two expected ones. The data obtained indicate an extreme lability of the expression of fragile site (X) (q 27) in consecutive lymphocyte generation.
mesh_terms: D002453:Cell Cycle; D002478:Cells, Cultured; D002648:Child; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D005786:Gene Expression Regulation; D008040:Genetic Linkage; D014644:Genetic Variation; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics; D008214:Lymphocytes / Q000166:cytology; D008297:Male; D011123:Polyploidy; D014960:X Chromosome
vernacular_title: Izmenchivost' ékspressii lomkogo uchastka khromosomy fra(X) v dvukh posledovatel'nykh kletochnykh tsiklakh.