During his career, he was instrumental in forging links between medicine and basic science, recognising that many disorders have a molecular origin. He also played a key role in setting up long-term research partnerships with communities affected by thalassemia across the world, and his book on blood disorders is regarded as the definitive text in this field.
Thalassemia is an inherited blood disorders where the body makes fewer healthy red blood cells and less haemoglobin than normal. Individuals with this condition can have mild or severe anaemia.
Haemoglobin plays a key part in carrying oxygen from the lungs to the rest of the body, and scientists now know that this consists of four protein chains - two alpha globin and two beta globin. Six genes are needed to make enough of these chains, four for the alpha chain and two for the beta chain.
Thalassemia is divided into two main types, alpha and beta, and these relate to defects in the respective chains. People with alpha-thalassemia can have one or more missing genes, and have moderate or severe anaemia, depending on the number of missing genes. Individuals with beta-thalassemia have one or both genes altered.
When this hypothesis was proposed, scientists were unable to separate the two chains, but Professor Weatherall and his team developed a method to separate them and measure the relative rates of production of each chain. Therefore proving that the disease was caused by an imbalance in the production of each chain.
Professor Weatherall and his colleagues went on to define a number of other blood disorders, and he is also credited with describing the first gene deletion directly linked to human disease, a severe form of thalassemia where infants are stillborn because they were unable to produce the alpha chain of haemoglobin.
Professor Weatherall and his researchers also helped develop prenatal genetic screening for thalassemia, and improved treatments for children with the condition. Blood transfusions were found to control the symptoms of thalassemia, but over time, this leads to a build up of iron in the blood which can lead to heart failure when children reach their mid-teens. He and his team were able to adapt an existing technique which removed the excess iron, known as 'chelation-therapy' so that children could be treated as they slept.
Professor Weatherall has helped improve the lives of people with thalassemia throughout the world and this award is a testament to that work.