Intermediate Technical In the Industry Vocabulary Test

variant of unknown significance

A genetic alteration whose clinical relevance and pathogenic potential have not been established.

Full Definition

A variant of unknown significance (VUS) is a genetic change identified through sequencing that cannot be definitively classified as pathogenic or benign based on current scientific knowledge. In cancer genomics, VUS findings present challenges for clinical decision-making as their role in cancer development or treatment response remains unclear. These variants require careful interpretation and may necessitate additional functional studies, family testing, or longitudinal follow-up to determine their clinical significance. The classification of variants can change over time as new evidence emerges from research and clinical experience.

Usage

Usage note: Abbreviate as VUS after first use; emphasize uncertainty in clinical interpretation.

In Context

"The genetic counselor explained that the variant of unknown significance required further evaluation." — Genetic counseling session
"Approximately 15% of variants identified were classified as variants of unknown significance." — Laboratory validation study

Also known as

VUS uncertain variant

Contrasted with

pathogenic variant benign variant

Don't confuse with

likely pathogenic variant actionable mutation

variant curation ← Back to glossary variant prioritization