Variant Annotation, Analysis and Search Tool
VAAST (the Variant Annotation, Analysis and Search Tool) is a probabilistic search tool for identifying damaged genes and their disease-causing variants in personal genome sequences. VAAST builds upon existing amino acid substitution (AAS) and aggregative approaches to variant prioritization, combining elements of both into a single unified likelihood-framework that allows users to identify damaged genes and deleterious variants with greater accuracy, and in an easy-to-use fashion. VAAST can score both coding and non-coding variants, evaluating the cumulative impact of both types of variants simultaneously. VAAST can identify rare variants causing rare genetic diseases, and it can also use both rare and common variants to identify genes responsible for common diseases. VAAST thus has a much greater scope of use than any existing methodology.
The VAAST package consists of three primary tools:
- VAT. The Variant Annotation Tool calculates a rich set of annotations on the effects that variants have on genomic features based on terms described and constrained by the Sequence Ontology. These effects, like synonymous and non-synonymous codon changes, stop-gain and loss, splice site variants and others provide additional information about the functional effect of a variant, which VAAST uses to score features.
- VST. The Variant Selection Tool performs set operations (intersection, union, compliment, and difference) on a group of annotated GVF files to produce a merged representation of the group's variants in a CDR file. VST can be used to simply create a merged set of variants for the target or background genomes required as input to VAAST, but can also manufacture arbitrarily complex selections based on nested set operations.
- VAAST. A probabilistic search tool that uses the outputs of VAT and VST to identify damaged genes and their disease-causing variants in personal genome sequences.
Note that another tool with the name VAT and similar functionality to VAAST's VAT was published recently by the Gerstein lab. You can access the Gerstein lab VAT on their web-site, however it's output is not compatible with VAAST.
- Matthew Herper - Forbes.com
- Salt Lake Tribune
- Ogden Standard Examiner
License & Downloads
VAAST was developed as a collaboration between the Yandell Lab at the University of Utah and Omicia, Inc. of Emeryville, CA. The University of Utah freely licenses VAAST for academic research use. For commercial, clinical and all other uses please contact Martin Reese at Omicia, Inc.
- License and Download VAAST
- VAAST Users Mailing List
- VAAST Quick Start Guide
- VAAST User's Guide
- VAAST Data Files