Gene Relationship
GET /api/genes/PRPF31/relationships/variant_set?format=api
{
    "data": [
        {
            "type": "SmallVariant",
            "id": "949"
        }
    ]
}
              GET /api/genes/PRPF31/relationships/variant_set?format=api
{
    "data": [
        {
            "type": "SmallVariant",
            "id": "949"
        }
    ]
}