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Marker chromosome


  • supernumary chromosome


A small chromosome containing a centromere occasionally seen in tissue culture, often in a mosaic state (present in some cells but not in others). A marker chromosome may be of little clinical significance or, if it contains material from one or both arms of another chromosome, may create an imbalance for whatever genes are present; assessment to establish clinical significance, particularly if found in a fetal karyotype, is often difficult.

Definition from: GeneReviewsThis link leads to a site outside Genetics Home Reference. from the University of Washington and the National Center for Biotechnology Information

See also Understanding Medical Terminology.

Published: February 8, 2016