Protein 'Fingerprint' Could Spot Alzheimer's in Living Patients
Right now, a true diagnosis comes only after death, researchers note
TUESDAY, Dec. 12, 2006 (HealthDay News) -- U.S. scientists say they've identified a panel of 23 protein biomarkers in cerebrospinal fluid that form a neurochemical "fingerprint" that may someday be used to confirm Alzheimer's disease in living patients.
Currently, doctors rely on their judgment to determine whether a patient has Alzheimer's instead of another form of dementia. In most cases, a true diagnosis can only be confirmed when brain tissue is examined after a patient dies, noted researchers at Cornell University and Weill Cornell Medical College.
"Our study is the first to use sophisticated proteomic methods to hone in on a group of cerebrospinal fluid biomarkers that are specific to autopsy-proven Alzheimer's disease. Those postmortem tests confirmed that the panel is over 90 percent sensitive in identifying people with Alzheimer's disease," Kelvin Lee, a professor of molecular and cell biology and an associate professor of chemical and biomolecular engineering at Cornell, said in a prepared statement.
The researchers compared 2,000 cerebrospinal proteins from 34 patients with autopsy-proven Alzheimer's to those from 34 age-matched people without Alzheimer's disease.
"Just as the human genome reflects the array of genes a person possesses, the 'proteome' is the vast collection of proteins expressed by those genes. Essentially, we used high-tech methods to contrast the proteomes of Alzheimer's patients against those of a control cohort that included people with other forms of dementia as well as healthy individuals, looking for key differences between the two groups," Lee said.
The findings are published in the December online issue of the Annals of Neurology.
"Typically, Alzheimer's disease is not diagnosed until the disease has already caused some amount of dementia. Having a chemical test available may allow patients to be diagnosed earlier in the course of the disease," lead author Erin Finehout said in a prepared statement.
A highly accurate biomarker test for Alzheimer's could help guide patient treatment and may prove valuable in research by helping scientists gauge the impact of treatments for the disease.
The U.S. National Institute of Neurological Disorders and Stroke has more about Alzheimer's disease.