The mutations affect the control of instructions for the body's output of a protein, amyloid, which causes dementia when deposited in the brain.
Dr Martin Rossor, head of the Department of Neurology at St Mary's hospital in west London, said today: 'This new finding will be of exceptional importance, because it will allow us to study patients with the disease accurately and to attempt to understand why the protein deposit causes the loss of memory and other distressing features of the illness. In some cases we may be able to predict whether someone is developing Alzheimer's at an early stage and to try new methods to prevent dementia.'
Scientists and doctors at St Mary's dementia team said the finding comes two years after the hospital showed that the first gene error was located on chromosome 21. This was the first indication of the true underlying cause of Alzheimer's. The second error, on chromosome 14, seems to occur in most of the remaining families with histories of Alzheimer's not accounted for by the mutation on the other gene site.
The other two groups reporting the finding are from the University of Antwerp, Belgium, and the University of Toronto, Canada. The St Mary's research and two other papers on the subject appear in this month's issue of the US magazine Nature Genetics.Reuse content