Among the 1,123 participants in the research were people who had Parkinson’s disease without a known cause; people experiencing pre-clinical symptoms of the disease, such as hyposmia, an inability to detect odors; and people who carried gene mutations that make them at higher risk for the disease but who had not yet shown clinical symptoms. People with no sign or risk of Parkinson’s also participated.
“The laboratory test, called the alpha-synuclein seeding amplification assay, detected alpha-synuclein in people’s spinal fluid with high accuracy,” says Dr. Salgado. “Alpha-synuclein is a protein in the nervous system, such as in the brain and spinal cord, and people with Parkinson’s disease have abnormal clumps of these proteins in their brain cells.”
For people with Parkinson’s, the brain cells that make dopamine, a chemical responsible for movement, also stop working or die, which can lead to unintended slowness of movements, tremors, stiffness, and difficulty with balance and coordination, among other clinical symptoms that worsen over time. While there is an imaging test to help detect dopamine loss, the research suggests the alpha-synuclein test can help detect Parkinson’s even before significant dopaminergic cell loss.
“The idea is to detect the abnormal proteins before people get advanced Parkinson’s disease that include these clinical symptoms,” says Dr. Salgado. “If we have this test to diagnose early, then we can work to institute various treatments against alpha-synuclein proteins. The laboratory test holds promise because the goal here is early detection and treatment development.”