title: Find DNA nucleotides anywhere is line
body: <p>I'm writing a perl script and I need to find letters of DNA (a,g,t,c) anywhere on the line.
  So far I have</p>
  
  <pre><code>while (FILE)
  { if ($_ =~ /[A+][G+][T+][C+]/)
  print "this is valid";
  }
  </code></pre>
  
  <p>I know this part needs to be fixed but I can't figure out what is wrong.</p>
  
  <p>Appreciate your time</p>