A ground-breaking gene bank which will pool the DNA and medical histories of thousands of people in Britain plans to start recruiting volunteers in 18 months' time.
The controversial UK Biobank is an ambitious project designed to produce a mass database to help in tackling many diseases such as cancer, heart disease and Parkinson's.
Volunteers will be tracked for decades
The organisers expect to begin looking for a representative sample of 500,000 middle-aged people aged 45-69 to volunteer a DNA sample and confidential health information next year.
These people will then be tracked for up to 30 years.
Project director Dr John Newton will spell out plans for the project to a meeting of MPs, academics and industrial leaders in London on Monday.
It will give us a profound insight into the relative roles of environment, lifestyle and inherited factors in the course of all the important causes of disease
The Commons Science and Technology Committee has expressed doubts about the wisdom of the project, claiming it may drain scarce resources away from other research for no guaranteed gain.
And the pressure group GeneWatch UK has called for an independent review of the project.
Dr Newton told the BBC: "It will give us a profound insight into the relative roles of environment, lifestyle and inherited factors in the course of all the important causes of disease which will help us to plan public health strategies for the next century."
The project will cost £45m over the first seven years. However, Dr Newton, former director of research at the John Radcliffe Hospital in Oxford, stressed that it would never cost more than approximately 1% of the total UK budget for medical research.
He said: "We think the benefits will be way out of proportion to the amount of funding.
"It will have different benefits at different stages of its lifecycle. Even as we start collecting the data the information will provide a tremendous insight into the patterns of health and disease for our UK population.
"But the really important benefits will come some 10-20 years down the line."
Dr Newton stressed that all volunteers would be free to withdraw from the project at any point.
He said: "All participants will be volunteers and will be kept fully informed of the project as it progresses. They will be free to withdraw at any point.
"Information provided by them will be confidential and samples and data will be held in an anonymised form and stored in accordance with the highest possible security and encryption standards.
"Samples and DNA will be stored centrally under the control of Biobank at all times.
"They will not be released to third parties, and will only be used for the stated purposes of the project: that is, for biomedical research and the public interest."