JavaScript生物信息_DNA序列分析处理

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function validateDNA(seq) {
  return /^[ATCG]+$/i.test(seq);
}
<p>function countBases(seq) {
const counts = { A: 0, T: 0, C: 0, G: 0 };
for (let base of seq.toUpperCase()) {
if (counts.hasOwnProperty(base)) counts[base]++;
}
return counts;
}</p><p>function complementStrand(seq) {
const compMap = { 'A': 'T', 'T': 'A', 'C': 'G', 'G': 'C' };
return seq.toUpperCase().split('').reverse().map(b => compMap[b]).join('');
}
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function findORFs(dnaSeq) {
  const startCodon = 'AUG';
  const stopCodons = ['UAA', 'UAG', 'UGA'];
  const rna = dnaSeq.replace(/T/g, 'U');
  const orfs = [];
<p>for (let frame = 0; frame < 3; frame++) {
for (let i = frame; i < rna.length - 2; i += 3) {
const codon = rna.slice(i, i + 3);
if (codon === startCodon) {
for (let j = i + 3; j < rna.length - 2; j += 3) {
const stop = rna.slice(j, j + 3);
if (stopCodons.includes(stop)) {
orfs.push(rna.slice(i, j + 3));
break;
}
}
}
}
}
return orfs;
}
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function sequenceIdentity(seq1, seq2) {
  if (seq1.length !== seq2.length) {
    const minLen = Math.min(seq1.length, seq2.length);
    seq1 = seq1.slice(0, minLen);
    seq2 = seq2.slice(0, minLen);
  }
  let matches = 0;
  for (let i = 0; i < seq1.length; i++) {
    if (seq1[i].toUpperCase() === seq2[i].toUpperCase()) matches++;
  }
  return (matches / seq1.length) * 100;
}
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function gcContent(seq) {
  const gcCount = (seq.match(/[GC]/gi) || []).length;
  return (gcCount / seq.length) * 100;
}
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