Mutations May Impact One’ s Type of Disease
No one with Parkinson’ s has the same disease experience. Even people with the same genetic mutation experience Parkinson’ s differently, such as showing different symptoms. There are some trends, though. A mutation in the PRKN gene, for example, is associated with young-onset Parkinson’ s( before age 50). Scientists are studying these known genetic connections and looking for other genes or biological or lifestyle factors that may influence when and how people get Parkinson’ s disease.
Genetic Testing Is Primarily for Research, Not Care
As of this writing, genetic testing for Parkinson’ s disease( PD) is most commonly performed in the context of a research study because results don’ t alter your personal medical care. If you have PD, finding out you have a mutation will not necessarily tell you about your future symptoms or disease course, nor will it impact which Parkinson’ s treatments you take. This may change as therapies targeting specific PD mutations move through the pipeline of clinical trials. And knowing your status can get you connected with genetic trials in the first place.
For those who don’ t have Parkinson’ s, interpreting genetic testing can be a bit tricky. Testing positive for a genetic mutation doesn’ t guarantee that you will develop PD, and different mutations raise risk to different degrees. On the other hand, a negative test does not mean you won’ t get Parkinson’ s. It’ s likely that many mutations linked to PD have not yet been discovered. And we have much to learn about how environmental factors interact with genetics to raise or lower the risk of PD.( See“ Parkinson’ s Genetics 101,” pg. 30.) Without a cure for PD or a way to prevent it, some people would rather not know their genetic information. Others, both with and without Parkinson’ s, have used this data to inform healthy lifestyles and participate in certain clinical trials.
Individuals pursue genetic testing outside of research— through their doctor or through an online service— for various reasons. People with PD might want to understand the likelihood of passing on a mutation to their children and those with an affected family member may be concerned about their own risk of Parkinson’ s. Sometimes people have no connection to Parkinson’ s and are simply curious about what information their genes hold.
Genetic Research Has Benefits and Risks
Some genetic studies look at one particular gene; others sequence all of your genes( i. e., your genome). Participating may involve little more than giving blood or providing a saliva sample, which sometimes can be done from your own home. If researchers need additional information to go along with genetic data, they may interview you over the phone, examine you in person or conduct other laboratory or imaging tests. During the informed consent process of these studies, all procedures, including how your genetic data will be collected and stored, and if your samples of genetic information may be used for future research, will be discussed. You’ ll also go over potential risks and benefits of participation, as well as whether you’ ll have access to your genetic results and a genetic counselor who can talk to you about the risks and benefits of genetic testing and research participation.( See“ What Is a Genetic Counselor?” pg. 37.)
Potential risks may center primarily on your genetic information. Test results, particularly if unexpected, may cause stress or anxiety. And although confidentiality and security are maintained to the highest levels, accidental data sharing may be a concern. In the United States, the Genetic
Information Nondiscrimination Act prevents employers and health care insurers from treating you unfairly based on your results. But these protections do have some important limitations.( See“ What to Consider before Genetic Testing,” pg. 36.) Other countries may have similar laws governing genetic information; check with your personal health care provider.
The decision to participate in any research is a personal one, but genetic research may bring additional considerations for you and your loved ones. A discussion with your doctor or genetic counselor can help address concerns you might have before deciding to participate in genetic testing or research.
Remember fact 4: Research Participation Brings Risks and Benefits.
34 Navigating Clinical Trials: A Guide for Parkinson’ s Patients and Families