Question: What is the main way DNA molecules mutate?

Reka Nagy answered on 9 Nov 2016:

Great question! There are indeed many ways in which DNA mutations can arise – one of these is through ultraviolet radiation from the sun, which damages DNA, causing it to be ‘misread’ by the proteins that copy it. This is why people who stay outside for a long time without using any sunscreen have a higher chance of developing skin cancer.

Read on for a bit more on DNA mutations, how they are repaired, and whether they affect every cell in the body or not!

Our cells have ‘proof-reading’ mechanisms in place that try to correct DNA mutations, but sometimes they are unable to find and/or correct these mistakes and the mutation persists.

Mutations acquired e.g. through UV radiation are only present in a few cells in the body – not in all of them. So while they may lead to skin cancer, these mutations will not be passed on to any children the person may have.

Sometimes, though, mutations can occur in what are called ‘germ’ cells – these are the cells that make the eggs and sperm that come together to make babies. If such a mutated cell is used to make a baby, all the baby’s cells will have the mutation, as all their cells came from this initial mutated cell.