WAS THIS KILLER DISEASE WRITTEN IN MY GENES?

OF COURSE I wonder why, at just 39, I had developed bowel cancer. It mainly affects people over 50, and by far the highestrisk age group is the over-80s.

Of the 42,000 Britons diagnosed with bowel cancer every year, just five per cent occur in the under-50s.

Half of all cases are related to lifestyle factors, such as not eating enough fibre, which helps food to move through the digestive system, and being very overweight. But in patients as young as me – who are fit and healthy – it’s unlikely this is the case, and genetic factors are far more likely to be at play.

In fact, studies show that up to a tenth of bowel cancers are related to genetics.

Studies show that people with a close relative, such as a parent or sibling, who gets the disease in middle age are much more likely to get bowel cancer early, but this wasn’t true for my family. So a few months after my diagnosis, I had a genetic test to look for answers.

Thankfully I didn’t have the well-known BRCA gene, which, as well as increasing the risk of breast, ovarian and prostate cancer, can raise the chances of bowel cancer. But I did carry another rare genetic mutation that doubled my chances of getting the disease early.

And it meant my children could be at a higher risk, too. They’d still have to be very unlucky – if they did inherit the gene from me (there’s a 50 per cent chance), they’d face a two in 10,000 chance of getting it in their younger years. But now we know, so when they’re adults they can be tested for the gene, and if they’re positive they’ll be screened regularly. And they now know it’s even more important not to smoke and – the most vital – eat plenty of fibre-heavy vegetables.