Parkinson's Clinical Trial Companion Navigating Clinical Trials | Page 31

Chapter 3 Genetics and Parkinson’s Research Some of the greatest strides in understanding Parkinson’s disease (PD) and developing new therapies have come from advances in genetics made possible by people who volunteered for clinical studies. Just 20 years ago, most scientists believed that unknown environmental factors were completely responsible for Parkinson’s disease. Then researchers collected and analyzed DNA samples from a large family, in which many members over several generations developed Parkinson’s. In these samples, scientists found the first gene (SNCA) linked to PD. It was a game-changing discovery that established a genetic connection to Parkinson’s and led to a new understanding: The clumps found in the brain cells of all people with PD (called Lewy bodies) are made mostly of the protein alpha-synuclein, which is made by the SNCA gene. Today, alpha-synuclein is a leading suspect in Parkinson’s disease. Many studies are looking to measure this protein as a way to diagnose and track Parkinson’s and to develop therapies to slow or stop its progression. Today, dozens of genetic mutations have been associated with an increased risk of Parkinson’s and scientists are tracking the ways they influence disease. We know, though, there is still much to learn. We can’t get there without a wide range of volunteers — people with PD, their family members and people without PD. Compared to other clinical research, genetic