Alzheimer’s marker yields blood test
By Janet Raloff
From Washington, D.C., at the Experimental Biology 2007 meeting
Despite memory-test and brain-imaging advances in recent years, diagnosis of Alzheimer’s disease remains a challenge. Usually, only the presence of clumps of the protein amyloid-beta in the brain at autopsy confirms that a person’s dementia was Alzheimer’s. A study in mice, however, suggests that a test for excess amyloid-beta in the blood could signal Alzheimer’s even before any symptoms show up.
If the scientists can adapt the test for use in people, Alzheimer’s screening might someday identify individuals eligible for preventive therapies, says Stina M. Tucker of the Johns Hopkins University School of Medicine in Baltimore. Such therapies, now under development, would slow the body’s amyloid-beta production or clear the proteins from the brain before cognitive impairment occurs.