VAF
Also written as: VAF — Variant Allele Frequency
Variant Allele Frequency, the proportion of sequencing reads supporting a specific genomic variant.
Full Definition
VAF (Variant Allele Frequency) represents the percentage or fraction of sequencing reads that contain a specific variant compared to the total number of reads covering that genomic position. VAF is crucial for determining variant quality, assessing tumor purity, and identifying subclonal populations in cancer samples. In cancer genomics, VAF can indicate clonal versus subclonal mutations and help track tumor evolution. Editors must ensure VAF values are consistently formatted (as percentages or decimals) throughout documents and understand that low VAF may indicate technical artifacts or genuine subclonal mutations requiring careful interpretation.
Usage
Usage note: Use VAF consistently rather than mixing with 'allele frequency'. Specify whether values are percentages or decimals.
In Context
- "The KRAS G12D mutation showed a VAF of 42%, indicating a clonal alteration." — genomic analysis report
- "Low VAF variants (< 5%) were filtered out to reduce false positive calls." — sequencing methodology section