Dr Diana Eccles and her colleagues at the University of Southampton are to follow 2,000 newly-diagnosed patients under 40 for the next three years.

Dr Eccles wants to discover if women whose mothers and grandmothers had the disease survive longer than those who develop it by chance.

The team also hopes to find out more about why some young women with no family history of the disease get breast cancer.

We hope to be able to tell from small tumours both how serious the cancer will be and how best we can treat it Dr Diana Eccles, Southampton University

Dr Eccles, a senior lecturer in cancer genetics, has asked 35 hospitals and clinics around the country to take part.

Sufferers will be asked to give a sample of DNA and details of their medical history.

She said: "A lot has been learned about the development of breast cancer but most of the research so far has been on older women.

"We want to see if cancers in young women with genetic links respond differently to treatment.

Highest rate

"Eventually we hope to be able to tell from small tumours both how serious the cancer will be and how best we can treat it.

"We hope to profile the risk factors for each woman and offer an individual treatment regime."

Britain has the highest rate of breast cancer in the world, with one in 12 women developing the disease, most over the age of 50.

The �160,000 project is funded by the Wessex Cancer Trust and the private health provider PPP.