Question: how can you change DNA to make mutants

Elliot Jokl answered on 15 Jun 2016:

Thanks for the question!

There have been a few different methods in the past, but the most modern method is to use a technology called CRISPR/Cas9 DNA editing.

What you can do is design a molecule which will only stick to the part of the DNA you want to mutate. This molecule will then call in an enzyme that breaks the DNA. When this happens, the cell tries to repair the DNA, but it will almost always make mistakes when trying to put the DNA back together again, and these mistakes are the mutations. Most mutations will cause a gene to stop working. If you look on my profile page, you will see an example with some fish embryos where I have mutated the gene that makes the dark splotches of pigment. The mutated embryos can’t make this pigment any more so they are see-through!

Another clever thing you can do is provide a bit of DNA sequence for the cell to use as a template when it puts the DNA back together. This lets you decide exactly what changes you want to make to the DNA, which is very useful if you want the mutation to have a specific effect.