Eyes hold Alzheimer's disease clue

Doctors could get an early indication that someone is developing Alzheimer's disease by examining their eyes, new research has suggested.

The illness leaves protein deposits in the eyes which could alert medical practitioners, scientists have found. Early diagnosis could be triggered by looking into people's eyes for the protein, which also accumulates in the brain.

A major impact on the treatment success of Alzheimer's can be gained by confirming Alzheimer's before the disease reaches an advanced stage.

The discovery emerged from a study of Down's syndrome patients, who often develop Alzheimer's symptoms by the age of 30.

Progress of the disease is accelerated in people with Down's because they have an extra copy of a key Alzheimer's gene.

Scientists found that a toxic Alzheimer's brain protein, amyloid-beta, shows up at a very early stage in the eyes of Down's patients.

The protein leads to cataracts, which were previously associated with Down's but not known to contain amyloid-beta.

The researchers, whose findings are reported in the journal Public Library of Sciences One, are now working on ways to detect tiny traces of the deposits in the eyes of ordinary patients.

Study leader Dr Lee Goldstein, from Boston University School of Medicine in the US, said: "Effective treatments for the brain disease in Down syndrome and Alzheimer's disease are on the horizon and early detection is the key to successful intervention."

Copyright Press Association 2010