- It’s very rare for Parkinson’s to run in families.
- The vast majority of people have what is called ‘idiopathic Parkinson’s’, meaning that there’s no known cause.
- However, for a small minority of people with Parkinson’s, there is a genetic link.
We all have two copies of 23,000 genes. Together, these genes (our ‘genome’) act as a blueprint that makes us who we are. Subtle variations make every person’s genome unique, and make us all different. We get half our genes from our mother and half from our father.
Sometimes, a gene has a difference (a ‘variant’ or ‘mutation’) that means the protein it produces doesn’t work as well as it should. This can increase someone’s risk of getting a particular illness.
It’s very rare for a health condition to be caused by a change in a single gene. Like most of our characteristics, our health is generally the result of a mixture of different genes with other factors such as diet and exercise.
Parkinson’s caused by genetic factors is extremely rare, but does happen sometimes:
- Some people with Parkinson’s carry a very rare change in a gene that causes the condition directly. People diagnosed with Parkinson's at a younger age are more likely to have a genetic link. Changes have been identified in genes including alpha synuclein, parkin, PINK1, DJ-1, ATP13A2, PLA2G6, FBXO7 and VPS35, and often cause symptoms to develop at a young age.
- A change in the LRRK2 gene known as G2019S is probably the most common genetic variant linked to Parkinson’s. In the UK, around one in 100 people with Parkinson’s carry it. It’s more common in North African and Jewish populations. People who carry this variant may develop the condition later in life and have around a 70% chance of being diagnosed by the age of 80.
- As well as single genetic changes that directly cause the condition, we now know that there are also changes that increase risk. The most common of these is having a variant in the GBA gene. These changes are more common but their effects are more subtle. Carrying one of them means you are more likely to develop Parkinson’s but often only very slightly.
It’s very rare for people to pass Parkinson’s on to their children.
Even if your Parkinson’s is in part caused by the genetic factors mentioned above, it’s far from certain that you would pass the relevant genes on to your children.
However, there are some cases where it does seem that Parkinson’s has been passed from one generation to the next.
The alpha-synuclein gene provides instructions for making a small protein called alpha-synuclein. This protein is found throughout the body, including in the brain. Research suggests that changes in this gene may play a role in the development of Parkinson’s.
We all carry two copies of most genes. A ‘carrier’ (or genetic carrier) is a person who has inherited a change in one copy of the gene, but does not have the symptoms of the genetic disease related to this change.
Advice and support given to parents about the risks of their child developing conditions with a genetic cause.
The branch of medicine that involves the diagnosis and management of hereditary disorders.
Genetic risk factor
A risk factor is anything that can increase your chance of developing a condition. A genetic risk factor comes from your genes.
The study of the role of genes in the development and function of the nervous system (brain and spinal cord).
Straight from the expert
Dr Patrick Lewis researches inherited Parkinson's at the University of Reading.
In this video, we asked him to give a simple explanation of whether Parkinson's runs in families.
Donna was told she had Parkinson’s in her early forties – the third woman in three generations of her family to receive the diagnosis.
"I was convinced everyone had it wrong and that Parkinson’s was just an easy diagnosis to label me with because of my mum and my nan."
Last updated March 2019. We review all our information within 3 years. If you'd like to find out more about how we put our information together, including references and the sources of evidence we use, please contact us at [email protected]