Characterization of neo-centromeres in marker chromosomes lacking detectable alpha-satellite DNA

Theresa W. Depinet, Joleen L. Zackowski, William C. Earnshaw, Sara Kaffe, Gurbax S. Sekhon, Richard Stallard, Beth A. Sullivan, Gail H. Vance, Daniel L. Van Dyke, Huntington F. Willard, Arthur B. Zinn, Stuart Schwartz

Research output: Contribution to journalArticlepeer-review

130 Scopus citations


Recent studies have implicated α-satellite DNA as an integral part of the centromere, important for the normal segregation of human chromosomes. To explore the relationship between the normal functioning centromere and α-satellite DNA, we have studied eight accessory marker chromosomes in which fluorescence in-situ hybridization could detect neither pancentromeric nor chromosome-specific α-satellite DNA. These accessory marker chromosomes were present in the majority of or all cells analyzed and appeared mitotically stable, thereby indicating the presence of a functional centromere. FISH analysis with both chromosome-specific libraries and single-copy YACs, together with microsatellite DNA studies, allowed unequivocal identification of both the origin and structure of these chromosomes. All but one of the marker chromosomes were linear mirror image duplications, and they were present along with either two additional normal chromosomes or with one normal and one deleted chromosome. Indirect immunofluorescence analysis revealed that the centromere protein CENP-B was not present on these markers; however, both CENP-C and CENP-E were present at a position defining a 'neo-centromere'. These studies provide insight into a newly defined class of marker chromosomes that lack detectable α-satellite DNA. At least for such marker chromosomes, α-satellite DNA at levels detectable by FISH appears unnecessary for chromosome segregation or for the association of CENP-C and CENP-E at a functional centromere.

Original languageEnglish (US)
Pages (from-to)1195-1204
Number of pages10
JournalHuman molecular genetics
Issue number8
StatePublished - Aug 1997

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Genetics(clinical)


Dive into the research topics of 'Characterization of neo-centromeres in marker chromosomes lacking detectable alpha-satellite DNA'. Together they form a unique fingerprint.

Cite this