Answers.Body: <p>If an inversion were just reversed then there would be 3' -> 3' bonds and 5' -> 5' bonds. That's why inversions are reverse complemented, you then maintain the normal 5'->3' direction. This is nicely covered <a href="https://biology.stackexchange.com/questions/44550/how-to-read-this-dna-inversion-diagram">over on our biology sister site</a>, which also includes this image:</p>
  
  <p><img src="https://i.sstatic.net/ijaLQ.png" alt="DNA inversion"></p>
  
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Answers.Text: Thanks for the link. The image you posted made it clear for me. The key is to look at both strands at the same time.
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Answers.UserDisplayName: Devon Ryan
Body: <p>I can’t quite understand the way inversions are defined. In particular I expect an inversion to be only a reversed version of the reference and not its reverse complement. Most sources use diagrams such as below which totally obscure the fact that it is also complemented.</p>
  
  <p><a href="https://i.sstatic.net/l6xbU.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/l6xbU.jpg" alt="enter image description here"></a></p>
  
  <p>Could someone provide an explanation on what causes an inversion and why it is defined the way it is?</p>
  
Tags: <ngs><structural-variation>
Title: Why are inversions defined as the reverse complement and not just the reverse of the reference?
ThreadText: # Why are inversions defined as the reverse complement and not just the reverse of the reference?
  
  (Asked by: username_0 on 2017-10-20)
  
  I can’t quite understand the way inversions are defined. In particular I expect an inversion to be only a reversed version of the reference and not its reverse complement. Most sources use diagrams such as below which totally obscure the fact that it is also complemented.
  
  [![enter image description here](https://i.sstatic.net/l6xbU.jpg)](https://i.sstatic.net/l6xbU.jpg)
  
  Could someone provide an explanation on what causes an inversion and why it is defined the way it is?
  
  **Tags:** ngs, structural-variation
  
  
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  ## 1 answers
  
  ### Answer by username_1 on 2017-10-21. Score: 6 | Accepted answer
  
  If an inversion were just reversed then there would be 3' -> 3' bonds and 5' -> 5' bonds. That's why inversions are reverse complemented, you then maintain the normal 5'->3' direction. This is nicely covered [over on our biology sister site](https://biology.stackexchange.com/questions/44550/how-to-read-this-dna-inversion-diagram), which also includes this image:
  
  ![DNA inversion](https://i.sstatic.net/ijaLQ.png)
  
  > **Comments:**
  > **username_0**: Thanks for the link. The image you posted made it clear for me. The key is to look at both strands at the same time.  
  
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