Thanks, can you explain more, I think the first option is more convenient (i.e. UpdateVcfSequenceDictionary https://gatk.broadinstitute.org/hc/en-us/articles/360042477832-UpdateVcfSequenceDictionary-Picard-)
Does this means that my command might look like :
gatk UpdateVcfSequenceDictionary -I oldfile.vcf -O newfile.vcf -SD referencegenome.dict
In such case, the input is the old VCF, outputing the newfile, and then I used the dictionarized fasta file of the reference genome ?
Thanks