The generic variant annotator (gvanno) is a software package intended for simple analysis and interpretation of human DNA variants. Variants and genes are annotated with disease-related and functional associations. Technically, the workflow is developed in Python, and it relies upon Docker / Singularity technology for encapsulation of software dependencies.
gvanno accepts query files encoded in the VCF format, and can analyze both SNVs and short insertions or deletions (indels). The workflow relies heavily upon Ensembl's Variant Effect Predictor (VEP), and vcfanno. It produces an annotated VCF file and a file of tab-separated values (.tsv), the latter listing all annotations pr. variant record. Note that if your input VCF contains data (genotypes) from multiple samples (i.e. a multisample VCF), the output TSV file will contain one line/record per sample variant.
December 29th 2023 - 1.7.0 release
April 27th 2023 - 1.6.0 release
--oncogenicity_annotation
- classifies variants according to oncogenicity (Horak et al., Genet Med, 2022)September 26th 2022 - 1.5.1 release
--vep_coding_only
- only report variants that fall into coding regions of transcripts (VEP option --coding_only
)Python
An installation of Python (version >=3.6) is required to run gvanno. Check that Python is installed by typing python --version
in your terminal window.
Other utilities
The script that installs the reference data requires that the user has bgzip
and tabix
installed. See here for instructions. The script also requires that basic Linux/UNIX commands are available (i.e. gzip
, tar
)
NOTE: gvanno should be installed on a MacOS or Linux/UNIX operating system
docker ps
or docker images
in the terminal windowInstall the assembly-specific VEP cache, and gvanno-specific reference data using the download_gvanno_refdata.py
script, i.e.:
python download_gvanno_refdata.py --download_dir <PATH_TO_DOWNLOAD_DIR> --genome_assembly grch38
NOTE: This can take a considerable amount of time depending on your local bandwidth (approx 20Gb pr. assembly-specific bundle)
Pull container images
Docker
Pull the gvanno Docker image (v1.7.0) from DockerHub (approx 3.8Gb):
docker pull sigven/gvanno:1.7.0
(gvanno annotation engine)
Singularity
--sif_file
in the gvanno.py
run script.The gvanno workflow accepts a single input file:
We strongly recommend that the input VCF is compressed and indexed using bgzip and tabix. NOTE: If the input VCF contains multi-allelic sites, these will be subject to decomposition.
Run the workflow with gvanno.py, which takes the following arguments and options:
usage:
gvanno.py -h [options]
--query_vcf <QUERY_VCF>
--gvanno_dir <GVANNO_DIR>
--output_dir <OUTPUT_DIR>
--genome_assembly <grch37|grch38>
--sample_id <SAMPLE_ID>
--container <docker|singularity>
gvanno - workflow for functional and clinical annotation of germline nucleotide variants
Required arguments:
--query_vcf QUERY_VCF
VCF input file with germline query variants (SNVs/InDels).
--gvanno_dir GVANNO_DIR
Directory that contains the gvanno reference data, e.g. ~/gvanno-1.7.0
--output_dir OUTPUT_DIR
Output directory
--genome_assembly {grch37,grch38}
Genome assembly build: grch37 or grch38
--container {docker,singularity}
Run gvanno with docker or singularity
--sample_id SAMPLE_ID
Sample identifier - prefix for output files
VEP optional arguments:
--vep_regulatory Enable Variant Effect Predictor (VEP) to look for overlap with regulatory regions (option --regulatory in VEP).
--vep_gencode_basic Consider only basic GENCODE transcripts with Variant Effect Predictor (VEP).
--vep_lof_prediction Predict loss-of-function variants with the LOFTEE plugin in Variant Effect Predictor (VEP), default: False
--vep_n_forks VEP_N_FORKS
Number of forks for Variant Effect Predictor (VEP) processing, default: 4
--vep_buffer_size VEP_BUFFER_SIZE
Variant buffer size (variants read into memory simultaneously) for Variant Effect Predictor (VEP) processing
- set lower to reduce memory usage, higher to increase speed, default: 500
--vep_pick_order VEP_PICK_ORDER
Comma-separated string of ordered transcript properties for primary variant pick in
Variant Effect Predictor (VEP) processing, default: canonical,appris,biotype,ccds,rank,tsl,length,mane
--vep_no_intergenic
Skip intergenic variants in Variant Effect Predictor (VEP) processing, default: False
--vep_coding_only
Only report variants falling into coding regions of transcripts (VEP), default: False
Other optional arguments:
--force_overwrite By default, the script will fail with an error if any output file already exists.
You can force the overwrite of existing result files by using this flag, default: False
--version show program's version number and exit
--no_vcf_validate Skip validation of input VCF with Ensembl's vcf-validator, default: False
--docker_uid DOCKER_USER_ID
Docker user ID. default is the host system user ID. If you are experiencing permission errors, try setting this up to root (`--docker-uid root`)
--vcfanno_n_processes VCFANNO_N_PROCESSES
Number of processes for vcfanno processing (see https://github.com/brentp/vcfanno#-p), default: 4
--oncogenicity_annotation
Classify variants according to oncogenicity (Horak et al., Genet Med, 2022)
--debug Print full Docker/Singularity commands to log and do not delete intermediate files with warnings etc.
--sif_file gvanno SIF image file for usage of gvanno workflow with option '--container singularity'
The examples folder contains an example VCF file. Analysis of the example VCF can be performed by the following command (Docker-based):
python ~/gvanno-1.7.0/gvanno.py
--query_vcf ~/gvanno-1.7.0/examples/example.grch37.vcf.gz
--gvanno_dir ~/gvanno-1.7.0
--output_dir ~/gvanno-1.7.0
--sample_id example
--genome_assembly grch37
--container docker
--force_overwrite
or Singularity-based
python ~/gvanno-1.7.0/gvanno.py
--query_vcf ~/gvanno-1.7.0/examples/example.grch37.vcf.gz
--gvanno_dir ~/gvanno-1.7.0
--output_dir ~/gvanno-1.7.0
--sample_id example
--genome_assembly grch37
--container singularity
--sif_file gvanno_1.7.0.sif
--force_overwrite
This command will run the Docker-based gvanno workflow and produce the following output files in the examples folder:
Similar files are produced for all variants, not only variants with a PASS designation in the VCF FILTER column.
Documentation of the various variant and gene annotations should be interrogated from the header of the annotated VCF file. The column names of the tab-separated values (TSV) file will be identical to the INFO tags that are documented in the VCF file.
sigven AT ifi.uio.no