title: fuzzy string matching with grep
body: <p>I am trying to match rows in a file containing a string say <code>ACTGGGTAAACTA</code>. If 
  I do</p>
  
  <pre><code>grep "ACTGGGTAAACTA" file 
  </code></pre>
  
  <p>It gives me rows which have exact matches. Is there a way to allow for certain number of mismatches (substitutions, insertions or deletions)? For example, I am looking for sequences</p>
  
  <ol>
  <li><p>Up to 3 allowed subtitutions like "AGTGGGTAACCAA" etc. </p></li>
  <li><p>Insertions/deletions (having a partial match like "ACTGGGAAAATAAACTA" or "ACTAAACTA")</p></li>
  </ol>