A recently-discovered genetic mutation could be used to combat the second largest cause of cancer deaths in the UK, scientists have said.
New research, published in the journal Science, suggests about one in 10 cases of bowel cancer is caused by a subtle difference in the activity of a pair of genes.
Experts believe bowel cancer, which claims nearly 50 lives a day in the UK, is most often caused by a combination of diet, lifestyle and hereditary factors.
Until now genes have been linked to about 5% of cases of the disease, but another 15-25% of people diagnosed with it have a family history of the condition.
Everyone inherits two copies of a gene, one from each parent, that usually produce equal amounts of a substance needed to make a protein that inhibits cell growth.
But for 29 of the people taking part in the study one of the genes was at least a third less active than the other.
Boris Pasche, director of the cancer genetics programme at Northwestern University's Feinberg School, said he expected a test for the genetic mutation to be developed for people with a family history of bowel cancer.