New Genetic Discovery Links ITSN1 to Parkinson’s Disease

Scientists have made a major breakthrough in understanding Parkinson’s disease, identifying a rare genetic mutation that can increase the risk of developing the condition by up to ten times. This discovery, focused on the ITSN1 gene, could open new doors for treatment and prevention. What Did Scientists Find? Researchers analysed data from nearly 500,000 people and found that mutations in ITSN1 impact how brain cells communicate. Since Parkinson’s disease is caused by problems with nerve signals in the brain, this link is a crucial discovery. Interestingly, similar mutations in ITSN1 have also been associated with autism spectrum disorder (ASD), hinting at a potential connection between the two conditions. Why Is This Discovery Important? Parkinson’s disease affects nearly 2% of adults over 65, making it the second most common neurodegenerative disorder after Alzheimer’s. Despite its prevalence, there is still no cure. Understanding the genetic risks behind it can help scientists develop better treatments. Dr. Ryan S. Dhindsa, one of the lead researchers, explained that individuals carrying rare ITSN1 mutations have up to a tenfold higher risk of developing Parkinson’s. Compared to other known genetic risks, such as mutations in LRRK2 and GBA1, the impact of ITSN1 is particularly strong. How Did Researchers Confirm the Findings? To ensure their results were accurate, scientists validated their findings across three large independent studies, including over 8,000 Parkinson’s patients and 400,000 healthy individuals. They also found that people with the ITSN1 mutation tend to develop Parkinson’s at an earlier age than others. What Does ITSN1 Do? ITSN1 plays a key role in synaptic transmission, the process by which brain cells send signals to one another. Since Parkinson’s disease is linked to problems with nerve communication, changes in ITSN1 could explain why symptoms like tremors, balance issues, and muscle stiffness develop. To further understand ITSN1’s role, scientists tested its effects in fruit flies. When ITSN1 levels were reduced, the flies showed worsened movement problems, similar to Parkinson’s symptoms. Researchers now plan to expand their studies to stem cells and mouse models. Could Parkinson’s and Autism Be Linked? Previous research has already suggested that people with autism spectrum disorder (ASD) are three times more likely to develop Parkinson’s-like symptoms later in life. Since ITSN1 mutations have now been linked to both conditions, this study supports the idea of a deeper connection between them. Scientists hope future research will shed more light on this relationship. What’s Next? This discovery highlights ITSN1 as a potential target for future therapies. By understanding how this gene affects the brain, researchers could develop new treatments to slow down or even prevent Parkinson’s disease. The study also demonstrates the power of large-scale genetic research in uncovering rare but important mutations that contribute to complex neurological disorders. As scientists continue to explore the role of ITSN1, this breakthrough brings hope for better treatments and a deeper understanding of Parkinson’s disease. This research was conducted by teams from Baylor College of Medicine, AstraZeneca, and the Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital. The study was published in Cell Reports on March 7, 2025.