The Variant Recoder, available on the Ensembl REST API, can help you with data re-use. Multiple identifiers, coming from different databases, can refer to the same variant – the Variant Recoder can help.Continue reading
By default, VEP uses the Ensembl/GENCODE transcript set when analysing your variants, but you can also choose to use NCBI’s RefSeq transcripts.Continue reading
Variants can be represented in myriad different ways; indeed, Ensembl VEP currently supports input in many different formats, including VCF, HGVS and SPDI. However, even within these specifications, variants can be described ambiguously. Insertions and deletions within repeated regions can be described at multiple different locations. For example, VCF describes variants using their most 5’ representation, while HGVS format describes a variant at its most 3’ location.
Starting in Ensembl 100, VEP optionally normalises variants within repeated regions by shifting them as far as possible in the 3’ direction before consequence calculation. This standardises VEP output for equivalent variant alleles which are described using different conventions.
The VEP can work as an offline or a web tool and it’s also available as REST service. Perfect for integrating into pipelines or displaying data on the web, the REST API VEP endpoints can take input as HGVS, genomic loci or variant identifiers and can interpret common forms of non-standard HGVS. They are all available using both GET and POST protocols, supporting queries on single or multiple variants respectively.
One of the biggest headaches when working with insertions and deletions is how many different ways you can represent the same variant. If you’re looking to find out if there’s already known allele frequencies or phenotypes at a locus, you want to make sure that you find the right one. The VEP can take that headache away through normalisation of variants.