A decade after the historic completion of the "book of life" - the first blueprint of human DNA - British scientists announced ambitious plans today to crack the personal genetic codes of 10,000 individuals.
Spread over the next three years, the "UK10K" programme launched by the Wellcome Trust charity will dwarf the original Human Genome Project.
Experts hope it will provide a much deeper picture of genetics than has emerged since the first draft of the genetic code, or genome, was published in June 2000.
One part of the £10.5 million project will completely sequence the genomes of 4,000 people who have already been studied for many diseases and traits over many years.
Another will focus on the gene-containing regions of DNA from 6,000 people with extreme obesity, neurodevelopmental diseases, and other conditions.
Principal investigator Dr Richard Durbin, from the Wellcome Trust Sanger Institute in Hinxton, Cambridgeshire, said: "Although genetics over the past five years has yielded a rich harvest of hundreds of variants associated with disease, much more remains to be discovered.
"We are seizing the chance to use technological advances in DNA sequencing to find variants that have even greater consequence for health."
The £2 billion Human Genome Project was an achievement compared with landing men on the Moon.
It took a publicly-funded international team of scientists 10 years to complete the sequence of chemical patterns in DNA that make up the genetic code.
They found themselves in a race with American genetics privateer Dr Craig Venter, who produced his own version of the genome using a different approach.
In the end, both crossed the finishing line at the same time and published simultaneous results in the journals Nature and Science.
Former Prime Minister Tony Blair and US President Bill Clinton announced the landmark achievement in a joint video address on June 26 2000.
Mr Clinton said: "It is now conceivable that our children's children will know the term cancer only as a constellation of stars."
But progress made since that remark has shown that he was being wildly over-optimistic. Despite big advances in technology, allowing genomes to be sequenced far faster and more cheaply than was possible 10 years ago, scientists are still scratching the surface of the highly complex world of genetics.
The new study is part of an ongoing effort to investigate the genome in more detail and uncover more of its secrets.
The 4,000 genome element will come from two important groups of volunteers comprising the TwinsUK and Alspac (Avon Longitudinal Study of Parents and Children) groups. Alspac includes more than 9,000 people originally from Avon in the South West whose health and progress has been monitored from birth in 1991/92. TwinsUK consists of 11,000 twins born in the UK, some of whom have taken part in studies for more than 18 years.
Studying these individuals will help researchers build a near-complete catalogue of genetic variations that can be tied to health effects.
Information from the second group will strengthen the findings about the genetic causes of disorders including severe obesity, autism, schizophrenia and congenital heart disease.
Gene-containing regions of the volunteers' genomes, known as "exomes", will be analysed using new cutting-edge techniques developed at the Wellcome Trust Sanger Institute.
Professor Tim Spector, who leads the TwinsUK project at King's College London, said: "We are fortunate in the UK to have such excellent collections of clinical samples provided by volunteers to help research and to help others.
"10,000 volunteers have contributed to this, the largest genome sequencing project so far undertaken. It's a stunning commentary on the generosity of participants in UK studies."
Sir Mark Walport, director of the Wellcome Trust, said: "The pace of technological change is extraordinary. We can now study the genome sequences of 10,000 people in three years. Just a decade ago it took much more time and money to decode just a single sequence. The involvement of clinicians, researchers and, most importantly, the thousands of people who have donated DNA samples, will help us to correlate genetic variation with individual variation in health and disease, and help to deliver on the long-term promise of the Human Genome Project."
:: Key players involved in the Human Genome Project today discussed its impact at the launch of a new gallery at London's Science Museum entitled "Who am I?".
They included Nobel laureate Sir John Sulston and Dr Francis S. Collins, director of the US National Institutes of Health, both of whom took part in the original announcement in 2000.
The Wellcome Trust funded one-third of the Project and was instrumental in ensuring that the data obtained remained in the public domain.
Sir John, director of the Wellcome Trust Sanger Institute from 1992 to 2000, who led the British arm of the Human Genome Project, said: "A key decision in the project, and one which has had a lasting legacy in science, was to release all data quickly as we went along.
"As a result, not only the human genome but many other genomes as well are freely available in the public domain, facilitating comparison and analysis of these immensely complex pieces of information. The Human Genome Project is widely regarded as a model for open science."
Dr Collins, who led the publicly-funded US scientists, said: "The First Law of Technology states that truly transformational technology will have its immediate consequences overestimated and its long-term consequences underestimated.
"Reflecting back on the announcement of the draft sequence in 2000, I think that law is coming true for the Human Genome Project. After a decade of hard work in the basic science of genomics, the health benefits are beginning to arrive. When I look across medical research - whether it is for cancer or heart disease or diabetes - I see researchers using the expanding array of tools that have arisen from the Human Genome Project.
"The leading edge of advances in diagnosis, prevention, and treatment has arrived, though the full flowering of genomic medicine still lies ahead."