Cancer gene discovered

Scientists in Britain say they've discovered a single gene that plays a key role in protecting people against cancer.

It works by producing an enzyme to break down cancer-causing toxins, such as those found in cigarette smoke.

The scientists say differences in the gene may explain why some people can smoke heavily throughout their lives without contracting cancer, while others are less fortunate.

They say that in the future preventative treatments may be developed to boost production of the protective enzyme in people with a high risk of contracting cancer.

From the newsroom of the BBC World Service