Our genes don’t predict our future

Steven Jones, Geneticist, makes his scientific case for why environment is a better predictor than genes of how our lives will go.

You’ve probably wondered, for most of your life, what your future might look like. Most humans do, and in pursuit of the answer have put forward several ideas on how one can predict, at the very least, whether they might get cancer or not. As an exceedingly clever race, we are constantly on the hunt for the elixir of youth- how can we live better? How can we live longer? How can we dodge disease? One of the ideas which has emerged from the search for the holy grail is that, somehow, DNA is the blueprint for our lives.

We have spent decades understanding how to pinpoint the genes for everything from terminal illness to alcoholism; and in so doing have come to believe that these physical and behavioural expressions are down to our genes. The ‘breast cancer’ gene has been thrust into the spotlight of late with famous faces, such as Angelina Jolie, having a double mastectomy in a bid to avert getting the same disease which took her mother, all because she carries “the gene for breast cancer”. It may seem an extreme reaction on her part but in many people’s minds, the reward outweighs the risk. However, this is not to say that you will or won’t get breast Cancer, but you might mitigate your chances to a small degree.

The real kicker is that, our DNA, does not in fact reveal answers to our biggest questions like “When will I die?”. Scientist have said that we can get an idea of when we will die by asking just a few simple questions- your age, your gender, do you smoke, are you obese etc. However, scientists are now saying that the blueprint of our lives lies not in our genes but in our environment- the biggest sole predictor of what’s to come. We now know we need to focus on society not biology; just by way of example, the life expectancy between the richest and poorest in Glasgow alone is 28 years; and what’s even more compelling is that life expectancy has been increasing by 6 years a day everyday since 1900 which is an even stronger case for nurture over nature.