Researchers recently added to the list of Parkinson's-associated genes when they identified mutations on TMEM230 linked to the disease. Discovery of this gene provides a new potential therapeutic target for PD treatment.
A group of scientists searched for differences in DNA (genetic information) between family members who had PD and those who did not in a recent study published in Nature Genetics. They identified mutations in TMEM230 as the cause of the disease in these individuals and confirmed these results in families in both Asia and North America, indicating that this gene may be linked to PD in patients of different ethnicities living in different environments.
The researchers also discovered that TMEM230 makes a protein that plays an important role in regulating synaptic vesicles, small packets in nerve cells that store and release neurotransmitters (chemical messengers that help cells in the brain communicate). TMEM230 mutations prevented these packets from working normally. These findings might explain why dopamine neurons do not function properly in individuals with PD.
"The protein that is abnormal in this genetic form of Parkinson's disease appears to be involved with vesicular trafficking and that is a roughly novel mechanism for Parkinson's disease, Joseph Jankovic, M.D., co-investigator of the study, director of the Parkinson's Disease Center and Movement Disorders Clinic at Baylor College of Medicine, and a member of the Scientific Advisory Board of The Michael J. Fox Foundation (MJFF). "As a result, that gives us some new possibilities of not only understanding the pathogenesis of Parkinson's disease but also maybe even developing disease-modifying targeted therapies.
Approximately 10 percent of PD cases have a genetic cause. Mutations in two other genes, SNCA and LRRK2, have also been causally linked to PD. Others, such as GBA, raise one's risk for Parkinson's but are not necessarily the definitive reason for Parkinson's onset. According to Dr. Jankovic, next steps include identifying more people with this mutation and performing additional studies to learn more about the underlying biology and clinical experience of this genetic form of PD.
Funding studies on the genetic causes of PD is a major priority of our MJFF strategy (although the Foundation did not support this particular study). We have developed roadmaps around SNCA and LRRK2 to enroll individuals with PD with these mutations in studies, interpret the underlying biology of these genes, create and share tools to advance this research, and develop new therapies.
Want to get involved in genetics research?
- We are currently investigating the role of SNCA, LRRK2 and GBA in our Parkinson's Progression Markers Initiative study.
- If you are an individual with PD and are of Eastern European (Ashkenazi) Jewish, North African Berber, or Basque ancestry, find out how you can participate.
Editor's note Feb. 2017: Want to learn more about genetics in PD? Sign up to watch our webinar.