Parkinson’s disease is a chronic disorder of the nervous system, which is made up of pathways of cells and neurons that send and receive signals throughout your body.

As of 2017, around 1 million people lived with Parkinson’s in the United States. And, according to the Parkinson’s Foundation, that number is expected to rise to 1.2 million by 2030 — each year, approximately 60,000 new diagnoses occur in the United States.

Parkinson’s disease is caused by the loss of nerve cells in a part of your brain called the substantia nigra. These cells control the production of the chemical dopamine. Dopamine helps control movement in your body. But when the cells are impaired, less dopamine is produced.

This condition isn’t fatal, but it can cause severe symptoms that impact everyday movement and mobility.

Hallmark symptoms include tremors and trouble with gait and balance. These symptoms develop because the brain’s ability to communicate is impaired.

Researchers aren’t yet certain what causes Parkinson’s. Read on to learn more about several factors that may contribute to the condition.

A 2020 study including 1,676 people with Parkinson’s in mainland China suggested that genes play a role in the development of the condition. An estimated 10 to 15 percent of people with Parkinson’s have a family history of the condition.

In fact, a number of specific genes have been linked to the development of Parkinson’s.

How do genetics factor into Parkinson’s in some families? According to Genetics Home Reference, one possible way is through the mutation of genes responsible for producing dopamine and certain proteins essential for brain function.

Some newer research from 2021 indicates that treatments could potentially be tailored to a person’s specific genetic background. However, more research has to first be done on genetic forms of the condition.

There’s some evidence that your environment can play a role in Parkinson’s disease. Exposure to certain chemicals has been suggested as a possible link to the condition. These include:

  • pesticides such as insecticides
  • herbicides
  • fungicides

It’s also possible that Agent Orange exposure may be linked to Parkinson’s, according to VA Health Care.

Parkinson’s has also been potentially linked to drinking well water in some older studies, such as one from 2009. However, a nationwide study from 2020 suggested that may not be the case. More research needs to be done to determine if well water is associated with increased risk.

Some research, such as a 2020 study performed in Morocco, also links consuming excessive manganese, a necessary trace mineral, to an elevated risk of Parkinson’s disease.

Not everyone exposed to these environmental factors develops Parkinson’s, though. Some researchers, such as the author of a 2017 study, theorize that a combination of genetics and environmental factors causes Parkinson’s.

Lewy bodies are abnormal clumps of proteins found in the brain stem of people with Parkinson’s disease.

These clumps contain a protein that cells are unable to break down. They surround cells in the brain and, in the process, interrupt the way the brain functions.

Clusters of Lewy bodies cause the brain to degenerate over time. This results in decreased motor coordination in people with Parkinson’s disease.

Dopamine is a neurotransmitter chemical that aids in passing messages between different sections of your brain. In people with Parkinson’s, the cells that produce dopamine are impaired.

Without an adequate supply of dopamine, your brain is unable to properly send and receive messages. This disruption affects the body’s ability to coordinate movement and results in trouble with walking and balance.

Aging also plays a role in Parkinson’s disease. Advanced age is the most significant risk factor for developing Parkinson’s disease, according to a 2014 research review.

Scientists believe that brain and dopamine function begin to decline as your body ages, per a 2016 review. This makes a person more susceptible to Parkinson’s.

A person’s sex can also play a role in Parkinson’s. According to 2014 research, people assigned male at birth (referred to as “men” in the study) are more susceptible to developing Parkinson’s than those assigned female (referred to as “women”).

The disease also seems to be more aggressive in males, per a 2020 review. Some researchers, including the authors of a 2015 research paper, are looking into whether sex-specific differences decrease with age.

Research from 2009 suggested that certain occupations may put a person at greater risk for developing Parkinson’s.

In particular, Parkinson’s disease may be more likely among people who have jobs in welding, agriculture, and industrial work. This may be because they’re exposed to toxic chemicals. However, study results have been inconsistent, according to 2010 research.

Ultimately, more research needs to be done.

Experts have some clues as to why Parkinson’s disease develops, but there’s still a lot that’s unknown.

Early detection and treatment are key in minimizing symptoms of Parkinson’s. Advanced technologies such as genetic research, stem cell research, and using so-called neurotrophic factors to revive brain cells show promise in exploratory research.

Though treatments can help you manage Parkinson’s symptoms and improve your quality of life, a cure hasn’t yet been found. And more research is needed to identify the exact role that genetics and environment play in causing this disease.

Much is still unknown about the causes and risk factors of Parkinson’s disease, but research is ongoing. It’s likely that environmental factors may play a role alongside genetic factors.

Being aware of your own risk factors and any potential early symptoms can help you work with a healthcare professional to come up with a plan for diagnosis and treatment.

There’s hope for new and more effective treatments and therapies to ease symptoms and improve quality of life.