Parkinson's disease does have a genetic component, but most people with Parkinson's do not inherit it from a parent

About 10 to 15 percent of people diagnosed with Parkinson's disease have a parent, sibling, or child with the condition. That means roughly 85 percent of cases appear without a known family history. When Parkinson's does run in families, the pattern is not straightforward — a parent with Parkinson's does not automatically mean their children will develop it, even if they carry the same genetic mutations.

Researchers have identified several genes linked to Parkinson's, including LRRK2, SNCA, and GBA. Inheriting one of these mutations increases risk, but it does not may provide the disease will develop. Other factors — age, environmental exposures, and possibly other genes — also play a role in whether someone actually becomes ill.

Key Takeaways

  • Most people with Parkinson's disease do not have a family history of the condition, even though genetics plays a role in some cases.
  • Inheriting a gene mutation linked to Parkinson's increases risk but does not mean you will definitely develop the disease.
  • If a parent or sibling has Parkinson's, your lifetime risk is higher than the general population, but still relatively low.
  • Genetic testing is available for some Parkinson's-linked genes, though results do not predict whether or when symptoms will appear.
  • Environmental factors, age, and other unknown factors influence whether someone with a genetic risk actually develops Parkinson's.

How genetics and environment work together in Parkinson's

Parkinson's is not a purely genetic disease and not a purely environmental one — it appears to require both. A person might inherit a mutation that raises their risk, but never develop symptoms. Another person with the same mutation might develop Parkinson's in their 50s or 60s. This suggests that something in their environment or life history — possibly exposure to pesticides, head injury, or other factors — triggered the disease in people who were already genetically vulnerable.

Scientists do not yet fully understand which environmental factors matter most or how they interact with genetic risk. This is why two siblings who share the same genes and grew up in the same house may have very different outcomes: one develops Parkinson's and the other does not.

What your family history tells you about your own risk

If you have a parent with Parkinson's, your risk of developing it during your lifetime is roughly 5 to 10 percent — higher than the general population (which is about 1 to 2 percent), but still a minority outcome. The risk is somewhat higher if multiple family members are affected or if the disease appeared at a younger age in your relatives.

Having a sibling with Parkinson's carries similar increased risk. If both your parents have Parkinson's, your risk is higher still, though even then it is not certain. Age matters too: Parkinson's is rare before age 50 and becomes more common as people get older, so your risk changes over your lifetime.

Genetic testing for Parkinson's-linked mutations

Genetic testing can identify whether you carry mutations in genes like LRRK2, SNCA, or GBA. Some people seek testing because they have a family history and want to know their genetic status. Others are tested after diagnosis to understand whether their Parkinson's has a known genetic cause.

A positive genetic test means you carry a mutation linked to Parkinson's, but it does not mean you will develop the disease. A negative test does not rule out Parkinson's — most people with the condition do not carry known mutations. If you are considering genetic testing, a genetic counselor or neurologist can explain what the results would and would not tell you, and help you decide whether testing is right for your situation.

Early-onset Parkinson's and family patterns

Parkinson's that appears before age 50 — called early-onset Parkinson's — is more likely to have a genetic cause than Parkinson's that starts later. If you or a family member developed Parkinson's in your 30s, 40s, or early 50s, the chance of a genetic link is higher, and family members may have higher risk as well.

Even with early-onset disease, inheritance is not always straightforward. Some families show a clear pattern where the disease passes from parent to child. Others have multiple affected members but no obvious inheritance pattern, suggesting the genetic picture is complex.

What to do if Parkinson's runs in your family

If you have a parent, sibling, or other close relative with Parkinson's, you do not need to take action based on that fact alone. There is no way to prevent Parkinson's, and no screening test that can tell you whether you will develop it. Some research suggests that regular exercise and cognitive activity may support brain health, but these are general wellness practices, not Parkinson's prevention.

If you develop symptoms — tremor, stiffness, slowness of movement, or balance problems — see a neurologist for evaluation. If you are interested in genetic testing or want to understand your family risk more clearly, talk with your doctor about a referral to genetic counseling. Genetic counselors can review your family history, explain what testing can and cannot tell you, and help you make informed decisions about whether testing fits your needs.

Frequently Asked Questions

If my parent has Parkinson's, will I definitely get it?

No. Even if your parent has Parkinson's, your risk is increased but not certain. Most children of people with Parkinson's do not develop the disease. Risk depends on whether your parent carries a known genetic mutation, your own genetic makeup, and environmental factors that are not yet fully understood.

Can I be tested to see if I will get Parkinson's?

Genetic testing can show whether you carry certain mutations linked to Parkinson's, but a positive test does not predict whether or when you will develop symptoms. There is no test that can tell you for certain whether you will get Parkinson's in the future.

What should I tell my children if I have Parkinson's?

You can explain that Parkinson's sometimes runs in families but most people with the disease do not pass it on. If they develop symptoms later in life, they should see a doctor for evaluation. There is nothing they need to do now based on your diagnosis alone.

Does Parkinson's skip generations?

Yes, it can. A parent might carry a gene mutation but never develop symptoms, while their child does. This happens because genetics is only part of the picture — environment and other factors also matter. It is also possible that someone in an earlier generation had undiagnosed Parkinson's.

Should I see a neurologist if Parkinson's runs in my family?

You do not need to see a neurologist just because of family history. See one if you develop symptoms like tremor, stiffness, slowness of movement, or balance problems. If you want to discuss your family risk or consider genetic testing, your regular doctor can refer you to a neurologist or genetic counselor.