title: X-chromosome instability in pluripotential stem cell lines derived from parthenogenetic embryos.
abstract: The karotype of six pluripotential stem cell lines derived from haploid and two additional lines derived from diploid parthenogenetic embryos is described. All these lines are diploid and possess a normal autosomal complement. The stage at which diploidization of the haploid cells occurs is not yet known. The XX-chromosome complement in these lines is unstable, although in two haploid-derived lines and one diploid-derived line many normal XX-bearing cells are found in early cultures. All of the lines so far examined either become XO (rarely), or a single X-chromosome shows a deletion in the distal region. The extent of this deletion varies between lines, but the position of the breakpoint appears to be constant for a given line. We suggest that these cytogenetic findings raise the possibility that a single deletion event occurring at an early stage during the isolation of these lines may confer a selective advantage to those cells carrying the deleted X chromosome.
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000648:ultrastructure*; D002460:Cell Line; D002478:Cells, Cultured; D002872:Chromosome Deletion; D004171:Diploidy; D005260:Female; D006238:Haploidy; D007621:Karyotyping; D051379:Mice; D008815:Mice, Inbred Strains; D010312:Parthenogenesis; D012730:Sex Chromosomes / Q000502:physiology*; D014960:X Chromosome / Q000502:physiology*