The first thing you need to know about predictive testing is that it is a tough decision for everybody. The reason for this, is because it is an emotive process where you are considering a number of factors that can be life changing. The information presented below is to assist you to make an informed decision that is right for you. When reflecting upon all the factors in relation to predictive testing, please be reassured there is no right or wrong answer, there is only the decision that is right for you at the right time.
What is Predictive Testing?
Due to the incredible collaborative efforts of HD patients who donated their DNA samples and the Huntington’s Disease Collaborative Research Group, the mutated Huntingtin gene was discovered in 1993. The discovery of the gene now meant we now had scientific evidence that if you inherit the mutated gene, you will develop HD. As a result, in 1993 the community had access to predictive testing that would identify whether you inherited the faulty Huntingtin gene, and would one day, exhibit symptoms of HD. The process of predictive testing includes extracting your DNA from a blood sample to identify whether you are carrying the faulty Huntingtin gene. However, the test cannot determine when symptoms will begin or how severe symptoms are likely to be.
What to expect?
The testing process usually includes the following steps but can vary in the number of appointments:
- An initial appointment with a genetic counsellor during which you may discuss the history of HD in your family, the genetics of HD, the reason that you’re seeking testing, and potential impacts of any test result
- A second appointment, which will include a blood test and potentially a neurological examination test if you decide to go ahead
- Another appointment once your test results are ready
- Follow up counselling support may also be required and is recommended by the genetic counsellor regardless of your test results
What is Genetic Counselling?
Genetic counselling is a supportive fact-based process that walks you through the genetics of HD, and also can explore your family history with you. In addition, genetic counsellors can assist you to explore IVF/PGD family planning options.
According to international guidelines, if you are 18 years of age or older and have a blood relative who has been diagnosed with Huntington’s disease, you are eligible for the genetic test. If you are under 18 years of age and have questions about testing, please get advice from your local Huntington’s disease association. However, in most cases, genetic testing is not legally permitted for minors even with parental consent.
Please note: It is ideal if you attend these appointments with a support person (i.e. spouse, sibling or friend etc). If you wish to have our support through this process, a Huntington’s Victoria representative can attend these appointments with you.