Search for minimum number of occurrences of a substring

Hello,

The following is the Body of the response:

{
    "downloadTime": "2021:03:17T17:52:21Z",
    "downloadTimeStamp": 1616003541,
    "genome": "hg38",
    "chrom": "chrX",
    "start": 51657026,
    "end": 51658026,
    "dna": "tatgacgtaactatccatttatttagatcatcctcaaaaatatctcagtacaattttcagtgtatagattttgccaccttttgtgagatttatccctaagtatttcatgtttttaatgttatcatgctggtatttttatttaaatatcaaattgtttgttagtaatatatagaacggcaagtgatttttatagatatagcaagggggttttttgcagattctataggattattttatagagatgatcacatcttcatagacaaaagagacagttttacttaccgctttccaagtttttcttctgacccttttattaacattttttcttgtattattgcactagttagattaagcggtggacaacatatttgcccacttttttttcattttaagaggtaagtactcagtcttcatcactacatttcaagttacctgtaggtttttcatagatgccatttccttatcaagttgaggaagattgcttctgtttctagtttggtaagagttttaccaggaatgaatgctggatttgccaaatgatgtttctgcgtctattaaaatgactattttacaaatctgttaatattgtgaattacattgatttgtttttctaaggttaaactacctttgcattctttggtcatgatgcattatccttttccccaggtaatactggcttcgtacaatgagtcaggaaatattccatttctttaattttctggaaaaaaaattctgtgggtggcattatttcttccttatatgattagtagaatccacaagtaaatccatctgggcctttaattttctttgtggaaggttttaaagtagaagcttaatgtattgaagagtgttttaatcacctcctatttatcccattagtgagggagggattcctgcctaggtttaggcaaatggctggcgtatgacacgacaccggacacatgagactgttagcaatttattagtaatgtatactcacaacctgagagaggaggatacc"
}

I have 2 questions:
1- I need to check if the β€œdna” contains at least 10 β€œNgg” sites. That means if there are a minimum of 10 [acgt]gg sites (agg or cgg or tgg or ggg). How do I write a test for that?

2- Is the following test for validating schema correct?

const schema = {
  "downloadTime": "data-time",
  "genome": "{{human genome}}",  //human genome is a collection level variable
  "chrom": ("chrX"|"chrY"),
};
pm.test('Schema is valid', function() {
  pm.response.to.have.jsonSchema(schema);
});

Many thanks for your help!

Answer for the first question:

const count = (str) => {
  const re = /[acgt]gg/g;
  return ((str || '').match(re) || []).length;
}

if (count(body.dna) >= 10) {
  // found 10 or more
}