For more than 20 years, researchers at Northwestern University have collaborated with a global network of scientists to try and unravel the mysteries of Parkinson’s disease. A study published this month in Nature Genetics shares an important discovery from that research. Not only does it offer insight into how the disease develops, it could change the way the disease is treated in the future.
There’s no cure for Parkinson’s disease, but researchers have learned that mutations in a gene called TMEM230 have been shown to cause the disease, the study states.
“It was completely surprising,” said Dr. Teepu Siddique, a professor at Northwestern University Feinberg School of Medicine who was one of the study’s researchers. “Its function was unknown.”
The discovery is significant because about 15 to 25 percent of Parkinson’s disease cases are believed to be caused by genetics, according to the Parkinson’s Disease Foundation. This is the third gene to be linked to the neurodegenerative disease that is characterized by symptoms such as tremors, stiffness and slowness of movement.
“It’s a progressive disease,” Siddique said. “There are symptomatic treatments that relieve symptoms—mainly the motor symptoms.”
Typically, Parkinson’s disease occurs late in life, with the incidence of occurrence increasing with age. Diagnosis before the age of 45, such as the late Muhammad Ali’s at the age of 42, is very rare, according to Siddique.
Discovering Gene TMEM230
This new genetic link came with its own mystery.
“This gene, it encodes a protein that has never been investigated before,” Siddique said.
Researchers discovered that TMEM230 encodes a protein that extends across the membrane of synaptic vesicles, which are tiny sacks that store neurotransmitters before they are released to other cells.
“We found that it is part of a membrane that surrounds synaptic vesicles that release the neurotransmitters that are decreased in this particular disease,” he said. “We think this is the first identification of a cross-membrane protein of synaptic vesicles of Parkinson’s disease.”