Variant in an interstitial undefined region fails validation

[leicray]

Describe the bug
An anonymous user submitted the variant description chr15:9459340_9459360dup (GRCh37) which resulted in an ERROR message to the sysops.

The 21-nucleotide duplication lies in chr15p11.2 in a region of undefined nucleotide sequence. For GRCh37 there is a sequence gap from 10001 to17000000. This ought to have been trapped by VariantValidator.

[Peter-J-Freeman]

On the next server update this will now give

{
    "flag": "warning",
    "metadata": {
        "variantvalidator_hgvs_version": "2.2.0",
        "variantvalidator_version": "2.2.1.dev709+g6340024",
        "vvdb_version": "vvdb_2024_8",
        "vvseqrepo_db": "VV_SR_2024_09/master",
        "vvta_version": "vvta_2024_09"
    },
    "validation_warning_1": {
        "alt_genomic_loci": [],
        "annotations": {},
        "gene_ids": {},
        "gene_symbol": "",
        "genome_context_intronic_sequence": "",
        "hgvs_lrg_transcript_variant": "",
        "hgvs_lrg_variant": "",
        "hgvs_predicted_protein_consequence": {
            "lrg_slr": "",
            "lrg_tlr": "",
            "slr": "",
            "tlr": ""
        },
        "hgvs_refseqgene_variant": "",
        "hgvs_transcript_variant": "",
        "primary_assembly_loci": {},
        "reference_sequence_records": "",
        "refseqgene_context_intronic_sequence": "",
        "rna_variant_descriptions": null,
        "selected_assembly": "GRCh37",
        "submitted_variant": "chr15:9459340_9459360dup",
        "transcript_description": "",
        "validation_warnings": [
            "This is not a valid HGVS variant description, because no reference sequence ID has been provided",
            "UncertainSequenceError: The submitted variant description NC_000015.9:g.9459340_9459360dupNNNNNNNNNNNNNNNNNNNNN refers to a genomic reference region with an uncertain base composition (N)"
        ],
        "variant_exonic_positions": null
    }
}