Gene Relationship
GET /api/genes/MAST4/relationships/variant_set?format=api
{
    "data": [
        {
            "type": "SmallVariant",
            "id": "1164"
        },
        {
            "type": "SmallVariant",
            "id": "1165"
        },
        {
            "type": "SmallVariant",
            "id": "1167"
        }
    ]
}