Epigenetics. What exactly is it?

Sally Le Page interviewed molecular biologist Nessa Carey to help us understand what exactly 'epigenetics' is and how our day-to-day life affects it.

Nessa - So everyone knows about the genetic code, which is DNA and which is very stable and doesn't change much during your life, on top of that there's additional information called epigenetics. It's a bit like if you think about a book and then you put post-it notes in the book to highlight certain things.

Sally - Or the worst, the people who draw on books with pens.

Nessa - Oh yeah. But there is a special circle of hell for those people. So we're going to leave those to one side. Basically you have this additional information written all over your genes, which controls how genes are expressed. Modern lifestyle, yes, will be affecting epigenetics so it will be changing that epigenetic system. Doesn't mean that's a bad thing. The epigenetic system is part of how we adapt to the environment around us. Huw's little toes would have been epigenetically altered by paddling in the Antarctic. I don't even go paddling in Norfolk; I don't know what the heck he was thinking. But anyway, everything that we do will be influenced in exactly the same way that people in the Middle Ages were epigenetically influenced by living with their pigs in their hovels, etc. It's just a way of adapting. People worry that we pass this epigenetic information on to next generations and under very rare circumstances maybe we do, other species do, but we don't need to worry about it in the grand scheme of things. The thing that is important is what you're experiencing at the time, so no need for epigenetic panic, there's a lot more things that I would panic about before I worried about epigenetics.