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Allelic variant of unknown significance


  • unclassified variant
  • variant of uncertain significance
  • VUS


An alteration in the normal sequence of a gene, the significance of which is unclear until further study of the genotype and corresponding phenotype in a sufficiently large population; complete gene sequencing often identifies numerous (sometimes hundreds) allelic variants for a given gene.

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

A variation in a genetic sequence whose association with disease risk is unknown. Also called variant of uncertain significance, unclassified variant, and VUS.

Definition from:  National Cancer Institute dictionaryThis link leads to a site outside Genetics Home Reference.

Related discussion in the Handbook

See also Understanding Medical Terminology.

Published: February 8, 2016