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Nikki J

Mar 22, 2012
Frequently asked questions about Familial ALS (FALS)

My relative had ALS. Am I at risk?
If it was one relative the answer is generally "no". The exception to this is if you also have, in the same bloodline, a relative with unusual dementia, especially younger onset and especially frontal temporal lobe dementia (FTD). FTD can be caused by the same defect that causes ALS You MAY be at increased risk

I have multiple relatives with ALS. What is my risk?

Most genetic ALS is so called autosomal dominant. This means that you only need to get the defective gene from one parent to be at risk for getting ALS. If your parent or your full sibling had the defect there is a fifty percent chance you got the defective gene. There is an equal chance you did not. If the relatives are more distant ( aunt or grandparent for example) and your parent's genetic status is not known then your parent would be the one with fifty percent risk. If your parent does not carry the defective gene it can not be passed to you.

So how I can I find out for sure?

If your family's genetic defect is known there is the possibility of testing ( see below). If the defect is not known and there is no living afflicted family member to test it is much more complicated. At this writing there are identified defects for 60-75 percent of FALS. To test for the whole panel is not usually covered by insurance if you are not having symptoms. Even worse, a negative test would not completely reassure you because there is the chance that your family defect is not among those tested. I would encourage you to discuss this with your doctor and consider a visit to a genetic counselor. Before you do this it would be wise to obtain what life insurance, long term care insurance and disability insurance you might need. Once your medical record reflects FALS it will be harder to get these at affordable rates, if at all. Watch this webinar for a geneticist's perspective ALS Trials | ALS Clinical Research | A User's Guide to Genetic Testing in ALS | Educational Webinars | For People with ALS & Caregivers | Northeast Amyotrophic Lateral Sclerosis (ALS) Consortium

I know my family defect. Should I test?

A very personal choice. If you are considering testing please get your insurances as noted above and see a genetic counselor. There is no right or wrong answer.
Things to consider:
Are you prepared for the result? Positive or negative it can be difficult. Those who test negative often experience survivor's guilt. A positive test can be devastating.
What will the results change in my life? Sometimes knowing one way or the other makes a practical difference such as a decision to have biological children. Sometimes a person just needs to know. At this writing if you are gene positive there are opportunities to participate in research (this may involve having multiple medical procedures ).
Only you can decide whether to test. For some, not knowing is more difficult than knowing. This was what I experienced. I worried less after finding I was gene positive in part because I was able to participate in genetic studies so I felt less helpless. I do know other gene positive people who regret being tested. It is really important to think very hard about this and to discuss with your significant other if any, with your doctor and with the genetic counselor. Once you have tested there is no going back.

I tested positive! Am I going to get ALS for sure?

This is something to discuss with the genetic counselor before testing and after. Different genetic defects have different penetrance ( that means how likely you are to get ALS if you have the gene) some are close to 100 percent but no one can tell you absolutely.

Is there any hope at all?
Yes there is hope. Research has come a long way especially in genetic ALS. They are starting to understand how the defects cause ALS and at this writing there are gene blocking therapies in trial for SOD1 , C9orf72,FUS and ATXN2 Sod1 is waiting for results and we are hoping for approval Even more exciting ( if possible) there is a prevention trial for SOD1 carriers. There are plans for a c9 prevention trial when 1 we have something that helps c9 PALS and 2 we have predictive biomarkers for impending c9 onset. Carriers can help by participating in genetic studies.
Disclaimer: this is not intended as medical advice. I am someone who is from a FALS family, had gene testing and went on to develop ALS. Please speak with your doctor and go to a genetic counselor to get advice for your specific situation.
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