The Wellcome Trust Case Control Consortium (WTCCC) is a collaboration of 24 leading human geneticists, who will analyse thousands of DNA samples from patients suffering with different diseases to identify common genetic variations for each condition. It is hoped that by identifying these genetic signposts, researchers will be able to understand which people are most at risk, and also produce more effective treatments.

The WTCCC has now searched for the genetic variation associated with tuberculosis, coronary heart disease, type 1 diabetes, type 2 diabetes, rheumatoid arthritis, Crohn's disease, bipolar disorder and hypertension. The research was conducted at a number of institutes throughout the UK, including the Wellcome Trust Sanger Institute, Cambridge University and Oxford University.

Researchers will have analysed over 19,000 DNA samples - two thousand patients for each disease and three thousand control samples - searching for important genetic differences between people who do and don't have each disease.

As a second project the WTCCC has also analysed 15,000 polymorphic markers that alter protein sequence to look for genetic variations relating to another four diseases - breast cancer, autoimmune thyroid disease, multiple sclerosis and ankylosing spondylitis.