one singularity container for seal's server, for instant annotation.
--> need to update the way to launch vep in seal
the singularity container one the cluster, for asynchronous, and may be bulk, annotations.
--> 1 - use only VEP annotated VCFs
--> 2 - use a directory to put unannotated VCFs, and wait for get VEP annotated VCFs complete files generated by a cron job on cluster.
It seems a good idea to use VEP docker image.
see : https://www.ensembl.org/info/docs/tools/vep/script/vep_download.html#docker