New clue to Alzheimer's found in form of protein

(AP) -- Researchers have uncovered a new clue to the cause of Alzheimer's disease. The brains of people with the memory-robbing form of dementia are cluttered with a plaque made up of beta-amyloid, a sticky protein. But there long has been a question whether this is a cause of the disease or a side effect. Also involved are tangles of a protein called tau; some scientists suspect this is the cause.