Researchers investigating the causes of breast cancer at the University of Cambridge claim to have identified four genes that raise the risk of the disease.
They made this breakthrough by using the new 'trawling technique', which allowed them to assess 200,000 blocks of DNA simultaneously instead of one by one.
They believe that their findings may help develop a screening programme in 12 to 15 years, in which the inherited risk of developing cancer can be assessed for every patient.
One of the new genes, when found in a mutated form, increases the risk of developing the cancer by up to 60 per cent, giving a woman a one in six chance of the disease.
Since its most damaging variant is carried by one in six women, the researchers say that it is much more common than previously identified genes that contribute to breast cancer.
Apart from its application to breast cancer, the new technique can be used for other types of the disease too, and the researchers have already started on applying it to prostate, bowel, and lung cancer.
Lead researcher Professor Bruce Ponder said that the technique should speed up the rate of gene identification enormously for a range of cancers.
"Previously scientists have had to search for new cancer genes one at a time, but we have been able to search two thirds of the genome in one go," Times Online quoted him as saying.
"Rather than fish for new genes one at a time with a rod and line, we have trawled the pool. This is not only a more efficient approach, it gets round the bias of previous studies in which scientists only examined genes they already knew something about," he added.
Although the genes identified in the latest research present a comparatively small-added risk of cancer developing in any woman who has mutated versions of them, they are much more common, and higher the chances of a woman developing breast cancer if she has the more mutated versions of any one of them.
The study, published in several papers in the journals Nature and Nature Genetics, has been hailed as "an outstanding discovery" that would "open doors across the globe" by the scientist fraternity.