## Breadcrumb - [Home](/) - [Resources & Support](/resources-support) - [Parkinson's Today Blog](/resources-support/blog) ## Breadcrumb - [Home](/) - [Resources & Support](/resources-support) - [Parkinson's Today Blog](/resources-support/blog) Raise Awareness # Parkinson’s Genes Explained: 5 Facts about LRRK2 Aug 04, 2026 ## 🧠 What will you learn in this article? This article describes 5 facts about *LRRK2*, a gene related to Parkinson’s disease: - *LRRK2* variants are changes in a Parkinson’s-related gene called *LRRK2*. These variants can change how brain cells function. - These changes can increase a person’s chance of getting Parkinson’s later in life. - Certain ethnic and ancestral groups have a higher chance of having a *LRRK2* variant. - Researchers are closely studying *LRRK2* to find new treatments for PD. ![DNA double helix](/sites/default/files/styles/no_sizing/public/images/lrrk2-blog-0826-hero.jpg?itok=q8yHnsxI) Genes are the instructions for making the proteins that give us individual characteristics. Just as genes influence traits like eye color or height, sometimes there are changes to a person’s genes — called genetic variants or mutations — that increase the risk of developing certain diseases. In some people, Parkinson’s disease (PD) can be linked to genetic factors. The [PD GENEration: Powered by the Parkinson’s Foundation](/advancing-research/our-research/pdgeneration "PD GENEration: Powered by the Parkinson’s Foundation") genetics study found that about 1 in 8 participants has a genetic variant related to Parkinson’s. This blog outlines five facts about one of the genes examined in PD GENEration, *LRRK2*, and why studying it is important for the entire Parkinson’s community. ## The Genetics of *LRRK2* *LRRK2* (pronounced “Lark Two”) stands for Leucine-rich repeat kinase 2 and was discovered in 2002. Since then, studies have shown that variations in this gene are related to developing Parkinson’s disease. Everyone inherits two copies of the *LRRK2* gene — one from each parent. Changes in *LRRK2* follow a [dominant](/understanding-parkinsons/causes/genetics/understanding-genetics "Understanding Genetics") inheritance pattern, meaning a variant in just one copy of the gene can increase a person’s risk for Parkinson’s disease. However, these variants also have “reduced penetrance,” which means that the gene doesn’t act alone to cause Parkinson’s. Whether someone with a *LRRK2* variant eventually develops Parkinson’s depends on a combination of genetics and other factors like age and environment. Some people carry a *LRRK2* variant but never show symptoms of PD. ### 1. *LRRK2* variants are a common genetic contributor to developing late-onset Parkinson’s. [PD GENEration](/advancing-research/our-research/pdgeneration "PD GENEration: Powered by the Parkinson’s Foundation"), the international research study providing genetic testing and counseling at no cost for people with PD, looks for changes in several Parkinson’s-related genes including *LRRK2*. To date, PD GENEration has found that: - 12% of participants have a variant in one or more of the genes tested. - About 2% of participants have a *LRRK2* variant. ***LRRK2*** **is the most common genetic contributor to late-onset Parkinson’s disease (when Parkinson’s symptoms appear after the age of 50).** [Learn more about genetics and Parkinson’s](/understanding-parkinsons/causes/genetics) Most PD (with or without a variant) is considered late-onset, starting later in life and involving [changes](/understanding-parkinsons/movement-symptoms "Movement Symptoms") like slowed movement and shaking. The way Parkinson’s appears in people with a *LRRK2* variant does not look physically different than Parkinson’s in people without this change. Because of the similarities, researchers are investigating whether understanding *LRRK2* could open doors to new treatments for all people with Parkinson’s. ### 2. Certain ethnic groups are more likely to have *LRRK2* variants. Different ancestral and ethnic groups can have different risks for genetic diseases. Findings from PD GENEration show that 10.5% of people who identify as Ashkenazi Jewish, 4.0% of people who identify as Berber, and 3.8% of people who identify as Basque carried a *LRRK2* variant — compared to 1.2% of people who identified as having none of these ancestries. People with a higher chance of having a *LRRK2* variant can use genetic testing like PD GENEration to better understand their genetic makeup for themselves and their families. > “For me, it was reassuring to learn that I am a *LRRK2* carrier, because then I knew that we had a target. There are clinical studies I can participate in to help advance the field. Within a week of learning that I have a genetic variant, I was participating in research, and I’ve been participating in research ever since.” > > -Jessi Keavney, Parkinson’s Foundation Research Advocate ### 3. A variant in the *LRRK2* gene may make it harder for cells to clear out unwanted material. The *LRRK2* gene gives cells instructions to make the LRRK2 protein, which is responsible for powering the cell and directing nutrients and waste. A variant in *LRRK2* can make the protein too active, disrupting the way a cell’s materials are normally transported. [Research suggests](/living-with-parkinsons/stories/tatyana-bodrug "Tatyana Bodrug, PhD") that while *LRRK2* normally helps cells clean up and recycle waste, *LRRK2* variants may stop this system from working properly. Waste can collect in cells — including in brain cells called neurons. When this happens, the buildup can lead to inflammation and cell death. [Early Parkinson’s symptoms](/understanding-parkinsons/10-early-signs "10 Early Signs") appear after the loss of neurons that make dopamine, a chemical that helps the body coordinate movement. ### 4. *LRRK2* is a target for new PD treatments. Scientists are highly focused on how mutations in the *LRRK2* gene influence Parkinson’s disease. By developing treatments to calm or quiet an overactive *LRRK2* gene, researchers hope to protect brain cells and potentially slow or halt the progression of Parkinson’s. There are several [active clinical trials](https://clinicaltrials.gov/search?cond=Parkinson%27s%20Disease&term=LRRK2&aggFilters=status:not%20rec&viewType=Card) — studies that test new treatments — for therapies targeting *LRRK2* in Parkinson’s. Some studies require a confirmed *LRRK2* variant, which can be verified with clinical-grade genetic testing like PD GENEration. For those who have already participated in PD GENEration, our [PD Trial Navigator](/about-us/news/pd-trial-navigator-launch "Parkinson’s Foundation Launches New Program to Accelerate Clinical Trials") program currently partners with [Neuron23](/about-us/news/pd-trial-navigator "New Parkinson's Foundation PD Trial Navigator Program Identifies 2,000+ Potential Participants for NEULARK Clinical Trial") for the Neulark trial for *LRRK2*. For more information about Neulark or other partner trials as they become available, email . ### 5. *LRRK2* breakthroughs could benefit the entire PD community. Even highly targeted genetic research has the potential to help broader communities. For example, research into a rare genetic condition called familial hypercholesterolemia (FH) helped scientists discover how the body regulates cholesterol. This led to the creation of statins, a medication that lowers cholesterol and is widely used today by people with and without FH. ## Enroll in Our Genetics Study Understanding the connection between Parkinson's and genetics can help us figure out how the disease develops and ultimately the best way it can be treated or cured. [EXPLORE PARKINSON'S-RELATED GENES](/advancing-research/our-research/pdgeneration/genetics-behind-pd "Current Findings from PD GENEration") [ENROLL NOW](/advancing-research/our-research/pdgeneration "PD GENEration: Powered by the Parkinson’s Foundation") Scientists are hoping *LRRK2* research may hold broader promise because of the similarities between *LRRK2*-related Parkinson’s and the more common idiopathic Parkinson’s — PD without a known cause. What they discover could help many people with Parkinson's in the future. ## Learn More The Parkinson’s Foundation works to improve care for people with PD and advance research toward a cure. Learn more with these resources: - Learn about and enroll in [PD GENEration](/advancing-research/our-research/pdgeneration "PD GENEration: Powered by the Parkinson’s Foundation") to find out if you have a *LRRK2* or another Parkinson’s-related gene variant. - Learn more about our [PD Trial Navigator](/about-us/news/pd-trial-navigator-launch "Parkinson’s Foundation Launches New Program to Accelerate Clinical Trials") program and the Neulark study, email . - Explore ways to get involved in the Parkinson’s Foundation, like becoming a [Research Advocate](/advancing-research/advocate-research "Advocate for Research") or by [sharing your Parkinson’s story](/living-with-parkinsons/my-pd-story/submit "Submit Your Story"). ## Related Materials Fact Sheets ### [ Genetics ](/library/fact-sheets/genetics) [Read Now](/library/fact-sheets/genetics) Podcasts ### [ Episode 73: Genetics and PD: What do we know so far? ](/library/podcast/73) [Listen Now](/library/podcast/73) Videos & Webinars ### [ Neuro Talk: Top Questions About PD GENEration ](/library/videos/pdgeneration) [Watch Now](/library/videos/pdgeneration) ## Related Blog Posts ![Scientist in a lab](/sites/default/files/styles/500x360/public/images/lrrk2geneticstherapy-blog.jpg?h=8240a2b1&itok=WFIS4Mci) Science News ### [ LRRK2 Genetics Therapy and Unintended Consequences ](/blog/science-news/lrrk2-genetic-therapy) READ NOW ![navigating genetic testing blog](/sites/default/files/styles/500x360/public/images/navigatinggenetictesting-blog-1.png?h=45815c72&itok=d-TEaN0-) Science News ### [ Navigating the World of Genetic Testing ](/blog/science-news/genetic-testing) READ NOW ![PD GENEration map of U.S.](/sites/default/files/styles/500x360/public/images/PDGENE-webinar-blogpreview.png?h=9105c3fe&itok=Q6j4-ocf) Advancing Research ### [ PD GENEration: Advancing Research, Empowering Lives ](/blog/research/pdgene-results-webinar) READ NOW [VIEW ALL BLOGS](/resources-support/blog) ### Join the PD GENEration Today PD GENEration is an initiative that offers genetic testing and genetic counseling at no cost for people with Parkinson’s disease. 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