Author: Madeleine Jepsen
Institution: Hillsdale College
A new mechanism for Parkinson's disease has recently been proposed by researchers studying the TMEM230 gene. This gene, which is involved in the transportation of neurotransmitters, is the first in its class to be implicated in the disease. The discovery has opened a new window for potential treatment options for those living with the disease.
Parkinson’s is a neurodegenerative disease characterized by progressively deteriorating motor function, manifesting as tremors, loss of balance, and slowed movement. Symptoms can also include muscle rigidity, changes in speech patterns, and loss of automatic movements such as blinking or smiling. According to the Parkinson’s Disease Foundation, an estimated seven to ten million people worldwide currently have Parkinson’s disease, since many cases go undetected in the early stages of the disease.
The underlying causes for the disease are still under investigation. Scientists have identified some genetic mutations that contribute to familial cases of Parkinson’s disease, but these represent only a small proportion of cases. Additionally, exposure to certain environmental toxins can increase the likelihood of contracting Parkinson’s - but this risk is fairly small.
Parkinson’s disease is characterized by neuron death. (Photo courtesy of Taylor Maley through Flickr Creative Commons)
On a cellular level, Parkinson’s disease is characterized by the death of nerve cells in the brain. Neurons are responsible for producing dopamine, one of the many neurotransmitters responsible for communicating signals between other nerve cells. When the neurons die, dopamine levels decrease, affecting areas of the brain responsible for movement.
The gene studied at Baylor College of Medicine in Texas, TMEM230, is linked to the tiny sacs —called vesicles — that help carry dopamine from neuron to neuron via synapses.
"By studying this new gene we will better understand how synaptic vesicle trafficking affects the development of Parkinson's disease," said the senior author Teepu Siddique, a renowned professor of neurology at Northwestern University’s Feinberg School of Medicine.
Although the gene mutation of TMEM230 was initially found through a family history; researchers have not ruled out the possibility that the gene could also contribute to other types of cases.
"This new gene could also be present in non-familial forms of the disease, which are the majority of the cases," said Joseph Jankovic, contributing author and professor of neurology at Baylor College of Medicine. "The discovery of TMEM230 provides new insights into the cause of Parkinson's disease and may lead to novel treatments for this and other neurodegenerative diseases."
While there is no cure for Parkinson’s disease, a variety of treatment methods exist to help manage symptoms. Pharmaceutical treatments aim to replenish the dopamine lost through neuron death, which help to decrease tremors and muscle rigidity. In some cases, surgery can also be used to treat symptoms. Understanding the genetic mechanisms responsible for symptoms will allow researchers to develop more direct and personalized treatments for those with Parkinson’s disease, such as gene therapy.
While further study of TMEM230 mutation is needed to make these potential treatments into a reality, the discovery of this gene's role in Parkinson's disease marks a major step toward understanding the underlying causes of the disease.