Analysis of chromosome 21 copy number in uncultured amniocytes by fluorescence in situ hybridization using a cosmid contig

Prenat Diagn. 1992 Nov;12(11):931-43. doi: 10.1002/pd.1970121113.


A comparison of the use of chromosome 21-specific libraries, DOP-PCR 21 paints, yeast artificial chromosome (YAC) clones, single cosmids, and a 21q cosmid contig as probes for the detection of the copy number of chromosome 21 in interphase cells by fluorescence in situ hybridization shows that the cosmid contig is a satisfactory probe for interphase analysis of chromosome 21. The contig cCMP21.a, which is 55 kb in length, is highly chromosome 21-specific and produces intense, compact signals in a high proportion of interphase cells. A retrospective blind analysis of coded uncultured amniotic fluid samples correctly detected four trisomy 21 cases out of 49 samples.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amniocentesis
  • Chromosomes, Fungal
  • Chromosomes, Human, Pair 21*
  • Cosmids*
  • Down Syndrome / diagnosis*
  • Female
  • Gene Library
  • Genome, Human
  • Humans
  • In Situ Hybridization, Fluorescence / methods*
  • Microscopy, Fluorescence
  • Polymerase Chain Reaction
  • Pregnancy
  • Restriction Mapping
  • Retrospective Studies