Researchers found that skin biopsies can reveal elevated levels of abnormal proteins associated with the two disorders.
The study is being released ahead of its presentation in April at the annual meeting of the American Academy of Neurology (AAN) in Washington, D.C.
The researchers took skin biopsies from 20 Alzheimer’s disease patients, 16 Parkinson’s disease patients, 17 patients with non-Alzheimer’s dementia, and 12 healthy people.
Compared to healthy people and those with non-Alzheimer’s dementia, the Alzheimer’s and Parkinson’s patients had seven times higher levels of a protein called tau. The researchers also found that Parkinson’s patients had eight times higher levels of a protein called alpha-synuclein, compared with healthy people.
As it stands now, a definite diagnosis of Alzheimer’s disease in a living person has not been possible, so the illness is often “unrecognized until after the disease has progressed,” Ildefonso Rodriguez-Leyva, MD, of the Central Hospital at the University of San Luis Potosi in Mexico, explained in an academy news release.
“We hypothesized that since skin has the same origin as brain tissue while in the embryo, that they might also show the same abnormal proteins,” he said. “This new test offers a potential biomarker that may allow doctors to identify and diagnose these diseases earlier on.”
American Academy of Neurology. Skin Test May Shed New Light on Alzheimer’s and Parkinson’s Diseases. News Release. February 24, 2015.