The start position of SV and CNVs at the gnomAD browser might be the preceding position

Hi gnomAD team,
The VCF specification (section 1.6.1) denotes the following for the position (POS) of structural variants (e.g. <DEL>) in the VCF file :

REF — reference base(s): (…) If any of the ALT alleles is a symbolic allele (an angle-bracketed ID String ) then the padding base is required and POS denotes the coordinate of the base preceding the polymorphism.

However I noticed that exactly the same position from the VCF file (that is the preceding base) is reported in the gnomAD browser as the position of the variant. For instance,


chr1    11000   gnomAD-SV_v3_DUP_chr1_7d73682f  N       <DUP>   999     PASS    ALGORITHMS=depth;CHR2=chr1;END=51000;...

Webportal: DUP_CHR1_7D73682F | gnomAD SVs v4.1.0 | gnomAD ( | 11000 - 51000

I wonder if the start position in the gnomAD browser should increase 1 bp to reflect the start position of the variant. Thank you very much


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