Parkinson ’ s Risk Factors continued
Carrying a Genetic Change Linked to Parkinson ’ s
Parkinson ’ s Risk Factors continued
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Carrying a Genetic Change Linked to Parkinson ’ s
When your DNA is implicated in Parkinson ’ s risk
If you have undergone genetic testing and learned you have genetic changes linked to Parkinson ’ s , there is plenty of reason for optimism . Even for people with the most common LRRK2 and GBA mutations , the chance of not getting Parkinson ’ s is much higher than the chance of getting the disease . And there are steps you can take that may limit risk , such as exercising , eating well and staying connected to others .
See page 12 for more .
What to know :
People pursue genetic testing for different reasons . Many are curious what their genes might reveal about health and habits . Others want to know about their risk for a specific disease , especially if a family member is affected . No matter why you get genetic testing , learning you carry a gene change linked to Parkinson ’ s can be worrisome , especially if no one in your family lives or lived with Parkinson ’ s .
Having a PD genetic change is not the same as having a family history of the disease . Some people carry a genetic mutation but don ’ t have any relatives with the disease . Others have multiple family members with Parkinson ’ s but no known genetic connection .
No matter which describes you , you may be wondering , “ What , exactly , does it mean to have a genetic mutation linked to Parkinson ’ s ?”
Let ’ s review the basics . Genes are bits of biological information passed down from ( biological ) parent to child . They set aspects of our appearance , personality and constitution throughout our lives . We all have the same set of genes — scientists refer to this set as the human genome . But depending on the DNA of our particular family and heritage , we have different changes in the structure of one or more genes . These are called genetic mutations or variants .
Some gene variants have no noticeable effect . Some lead to characteristic outward effects that make up the rich pageant of humanity in all its infinite variety . Still others — the ones that can cause us concern or even anxiety — play a role in our risk of getting a disease , such as Parkinson ’ s .
Parkinson ’ s is not a disease with a genetic “ smoking gun .” No known mutation leads to a 100-percent chance of causing PD . In other words : Having a genetic mutation linked to PD does not mean you will definitely get the disease . In fact , many people living with PD-linked genetic changes never go on to get it . ( And research has much to learn from these individuals . They may have other protective factors in their DNA that , if harnessed for drug development , could be the key to preventing Parkinson ’ s in everyone .)
It is likely that more genetic mutations linked to Parkinson ’ s remain to be discovered . Of those research has uncovered to date , most raise Parkinson ’ s risk only by a small amount . The most common occur in two genes called LRRK2 and GBA .
Your ethnicity and your genes
People of certain ethnic backgrounds , including those of Ashkenazi ( Eastern European ) Jewish and North African Berber descent , are more likely to carry Parkinson ’ s genetic mutations . Researchers believe this is because many people in these populations share a ( respective ) common ancestor .
The most common Parkinson ’ s gene changes — those that occur in the LRRK2 and GBA genes — are more frequent in these ethnic groups . The most common LRRK2 mutation , for example , occurs in approximately two percent of all people with PD . But this mutation is present in about 15 percent of people with PD who are Ashkenazi Jewish and in up to 40 percent of people with PD who are North African Berber . Similarly , GBA mutations happen in about 10 percent of people with PD overall , but in at least 15 percent of people with Parkinson ’ s who are Ashkenazi Jewish .
Better Brain Health | Section 02 — Understanding and Living with Risk Factors 33