Question: What causes genetic mutations?

Lilian Hunt answered on 12 Mar 2014:

So many things can cause genetic mutations but a lot of them can occur just by chance.

Every time one of your cells divide, your entire DNA has to replicate somehow and with so much information, it is likely your body will get it wrong sometimes. Think of it like if you had to re-write all of the Harry Potter books, you would make some mistakes somewhere? In our cells we also have molecules that help go back over the newly copied bits of DNA and check for mistakes. So that’s like if you got someone to read over you Harry Potter copies and check for mistakes. That would get rid of a lot of them, and mostly the big mistakes. But there would still be a few little mistakes left. Most of these wouldn’t make much of a difference, you could still understand the books if you accidentally spelt Hermione’s name wrong once in a while. That’s the same for your DNA. In some places, a mutation can be ok and not actually affect you. However sometimes there are points where a mutation can cause big problems.

The things in the environment that can cause genetic mutations can seem like a scarily long list but realistically you’re a t a fairly low risk if you live a healthy life. Some chemicals like those in cigarettes can cause genetic mutations which can cause cancer. The chemical that cause genetic mutations are called mutagens. If these mutagens can also cause cancer then they are carcinogens. There are some “physical” mutagens like x-rays (although don’t be worried if you go to a hospital as the risk is very very low!), radiation (although with not quite as extreme results as making anyone into a superhero) and UV rays like those from the sun (that’s why you should wear sunscreen on holiday!).