A £300 million "landmark" project to better understand the genetics of people with cancer and rare diseases is to be based near Cambridge.
The 4 year study will map the DNA of thousands of patients, helping doctors and scientists to find new drugs and treatments.
The research will be carried out at the Wellcome Trust's Genome Campus and The Sanger Institute.
The Prime Minister says the project is destined to make Britain the world leader in genetic research on cancer and rare diseases.
David Cameron made the prediction as he announced a package of deals that will secure the future of the work, expected to be completed by 2017.
Nothing on the scale of the 100,000 Genomes Project has ever been attempted anywhere before.
Over the next four years, about 75,000 patients with cancer and rare diseases, plus their close relatives, will have their whole genetic codes, or genomes, sequenced.
Cancer patients will have the DNA of both healthy and tumour cells mapped, making up the 100,000 total.
Scientists expect the project to be pivotal to the development of future personalised treatments based on genetics, with the potential to revolutionise medicine.
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