DNA testing to identify specific genes that may be associated with Migraine may seem like something in the future, however we actually have the capability for it today.
DNA testing today is usually done for one of three reasons:
- Because the doctor orders the test to look for and diagnose a specific Migraine equivalent.
- For a patient who wants to order their own limited DNA results from companies that currently provide them for public use.
- Because a Migraineur and their family members choose to participate in research to help pinpoint new genes associated with our disease.
It is possible for anyone to have your entire genome mapped, looking for specific issues you may have a predisposition to develop. However, that is a process that requires blood to be drawn and is typically available only to wealthy individuals because it is very involved and expensive. We are talking today about saliva testing and what it is like to go through the process itself.
About DNA testing
Most DNA tests require specific information from the patient called a Patient History.
A doctor ordering a test will do so only if they think there is benefit to having the specific information, and will ask you about your history and symptoms. This can be especially helpful if many members of a single family have similar symptoms that resemble the gene the doctor will test for. Because of the expense of these tests, it is very important that there is a very strong suspicion that the targeted gene will be found before the test is ordered. In this case, it is more often that a doctor is looking for something vs. looking to rule something out.
An individual looking to have their DNA profiled is often doing so because they want to be proactive in their health care, and having the knowledge that can lead to lifestyle changes and/or preparations is both comforting and powerful for the majority of patients who choose to go this route. In this instance, the profile will look at many genes, not just those associated with Migraine. The patient ends up with a very interesting list of conditions they may be predisposed to have — or not; conditions for which they may be a carrier; how they respond to specific medicines; and even their genetic hair and eye color or where their ancestors originated. Because the tests need to be specific, patients will fill out a detailed questionnaire about their lifestyle, medical and family history as they know it. Some patients may not be interested in learning about their status for specific conditions. You can ask to have specific results left out of your report.
A family or person looking to participate in genetic research will also be asked to fill out a detailed questionnaire which will help researchers as they look for commonalities and clues where they might look for DNA that might be affecting them. In some cases it might be possible for a patient to receive their DNA information at a later time, or copies of the study they are participating in. If the patient is interested in these things, asking before participation is key. Many research projects will not give you results to your DNA test however, so be prepared for that possibility.
Patients are given a kit in a box. The kit will have specific instructions written in easy language, often with instructional illustrations. Most patients are required to refrain from eating or drinking for an hour or two before participation.
Inside the kit is a clear plastic tube with an attached cap.
The patient is asked to spit into the tube until the saliva reaches a fill line toward the top. When full, the patient closes the lid which releases a liquid that mixes with the saliva in the tube. Gently inverting the tube a few times is usually required to mix it properly.
Once the saliva is in the tube and it has been securely closed, it will be put into a plastic bag from the kit and placed into a mailer then sent to the company for testing.
Receiving your results
In some instances, such as research trials, you may not receive any results.
If you will be receiving results, it may take several weeks to receive them. Most companies offer your results online after you have set up an account with them using the serial number from your kit. If so, you will receive an email notification when your results are ready and have been reviewed by a professional. If you have questions about your results, professionals are on staff and available to answer those questions, usually at no additional charge.
Sometimes doctors have ordered your DNA tests, and you will likely receive your results during a consultation with them or a genetics counselor. Full explanations are given and an opportunity to ask questions is a great time to educate yourself about your Migraines and your genetic predispositions.
Reading your results
Genetics are not a black and white science. Some conditions come with a single, very specific gene, however most conditions have several markers associated with it. Many of those markers must be *turned on* by something to function. Just because you have a marker that indicates a predisposition for a condition, doesn’t mean you will get it. Some markers seem to be protective of certain disorders/diseases.
With this in mind, it is more of an art to reading the results for a full impression of a patient’s risk for an inherited condition. You will not usually be told “You have this condition” unless you also have the symptoms that go with it and other conditions have been ruled out first. You will be told that you may be at increased or decreased risk for a condition, based only on the genes we can currently test for. Most companies who provide these tests are extremely good at explaining how to read your tests and will help you through the process.
When I had my DNA tested, I spent quite a while learning how to read the results before I ever received mine online, even though I had a slight background in understanding basic genetic principles from my days breeding Arabian show horses. That said, I could have much more easily contacted my assigned genetic counselor and had them all explained to me. I did ask one question via email and was very satisfied with the quick and thorough response.
Where can I get genetic testing?
Genetic testing is not for everyone. Even consumer testing comes with the potential to learn information you might not really want to know. The majority of people who choose genetic testing do not suffer increased anxiety as many physicians may fear however, but instead use the information they’ve gained to change their lifestyles in positive ways that might influence their medical predispositions in a positive way.
There are many places where genetic testing is available. Where you go will depend largely on what information you are looking for.
For example, if you desire testing for Familial Hemiplegic Migraine for which there are specific genes identified, you will need to talk to your doctor and have your (blood or saliva) sample sent to one of these labs: NCBI Gene Test Locations. Mutations in the CACNA1A, ATP1A2, and SCN1A genes have been found to cause the three known types of familial hemiplegic migraine.
If you want to order your own testing, there are a few companies who offer it including 23andMe.
Here is a nice resource at the Migraine Research Foundation if you’re interested in reading about recent research completed on genetics and Migraine. If you wish to participate in future genetics studies, keep an eye out on their projects for one that might fit, or monitor CenterWatch or other trial listings sites for future trials near you.
Disclosures: I have no financial or other interest in the companies or products mentioned.
Sources: 1. Familial Hemiplegic Migraine.” Genetics Home Reference. Available at: http://ghr.nlm.nih.gov/condition/familial-hemiplegic-migraine.February 25, 2013 2. Completed Research” Migraine Research Foundation. Available at: http://migraineresearchfoundation.org/completed-research.html. February 27, 2013