Getting a genetic test for familial Alzheimer’s disease at 25

This blog is a cross-post with The Huffington Post.

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When people hear the word Alzheimer’s, many envision an elderly person shut away in the depths of a care home.  As a 25-year-old, I was all too aware that young people assume that it’s a natural part of ageing, and nothing for them to worry about yet. But it’s not, it’s a brain disease that strips everything away from the individual – and it doesn’t just affect the elderly.

For an unfortunate few of us it’s something that will have a huge impact on our lives, from the second we’re born to the moment we die.

Around the world there are only a few hundred families who have been identified as having a rare, inherited form of the disease. Familial Alzheimer’s accounts for less than one percent of Alzheimer’s disease cases, and usually takes effect before the age of 65. For some, it is as young as 30.

My dad started showing the symptoms of Alzheimer’s when he was just 41, and I was just 11. His dad, grandmother, and dad’s cousin had already died from the disease, and his younger sister soon got it too. There is now a young generation of our family waking up to the reality that we’ll be next.

In my late teenage years I found out I had a 50% chance of inheriting early-onset Alzheimer’s – caused by a fault in the amyloid precursor protein (APP) gene – from my dad. I put myself forward for an observational research study called DIAN, on a yearly basis being given psychological tests, MRIs, PET scans and lumbar punctures – all in the hope that one day it would lead scientists to a cure.

Then came the prospect of genetic testing. A simple blood test could tell me if I had the faulty gene, and if I did I would be certain to develop the disease, up to five years either side of when my dad did. This would mean developing symptoms as young as 36. Or, I could be told I didn’t have the gene, in which case I would be like any other member of the population – free from its shackles.

For me, it was a no-brainer. I’d either get to live my life knowing I would not develop it, or I’d have a sense of control and certainty, knowing how I could plan my finances, plan a family, and mentally prepare for what was coming. But I’m in the minority – only 20% of those who have a genetic risk of dementia go on to find out their genetic status. Only 40% of those who go to a geneticist actually go through with the test. There are a number of reasons for this, and they’re important ones. There is currently no cure for dementia, and drugs on the market only treat the symptoms – they can in no way slow down the progression of the condition. Despite this, I still had to know.

It took three visits to the GP to be taken seriously. I was twice told to go away and ‘have another think’ before deciding, another issue for those wanting to get the test. I was probably assumed to be too young to not regret my decision. Unfortunately, because it is so rare, there was very little out there to help me decide. I sat on search engines trying to find a personal account of what it might be like. And that is why I’m writing this piece – so that others in the same position may see this article and feel more empowered to make the right decision for them.

I was finally referred to the clinical genetics department of my local hospital, where I was seen by a geneticist in September 2016. Every person will go through at least a couple of counselling sessions before being given their results. The first session was about my reasons for wanting to know and my current lifestyle, and the second in November involved talking to my partner and I about pregnancy options in relation to potentially passing on the gene to future children.

It was then I found out that if I did have the gene and wanted to ensure my children wouldn’t get it, having a child would be a lengthy and complicated process. I would have to go through preimplantation genetic diagnosis (PGD), which involves undergoing normal IVF treatment before checking the genes of embryos and transferring the unaffected ones to the womb.
After my second session, the geneticist felt I was ready to have the test, with being so sure of my decision, in a stable relationship, and aware of the implications with help from my place of work, Alzheimer’s Research UK. The test involved some blood being taken and sent off to a lab for analysis. After a gap for Christmas and moving into my first home, I came back on 22 February for my results.

Nothing could truly have prepared me for that moment. It’s life-altering, and for weeks before it I went into a strange state of mind – completely sure that I had it and unwilling or unable to think of the alternative. I thought about it all day, and would wake up repeatedly in the night with it at the forefront of my mind.

You often hear people talk about ‘life-changing experiences’ – but I don’t think I’ll ever enter a room again knowing that the next few words spoken will truly change everything.

I feared an X Factor-style pause for effect as the answer was given, but thankfully the genetic counsellor took less than five seconds after sitting down to say “you don’t have the gene.” I burst into tears at the unexpected result.

As I got up to leave, I felt only relief. But the genetic counsellor said: “Believe me, you’ll feel up and down for a good couple of weeks.”
He wasn’t wrong – there is an intense survivor’s guilt when you find out you don’t have the gene but your siblings and other relatives are still at risk. I’d been in the same boat as my sister my entire life, with both of us potentially facing this terrible fate together. Now I’d abandoned her to face it on her own. Telling my family was extremely hard despite the seemingly good result.

Six months later, the news has sunk in. It’s hard to know what it would have been like if I did have the gene. I would hope for those who have got a positive result, it would bring them some relief or calm to be given some certainty, and help them plan for the future.

In July, London hosted the Dominantly Inherited Alzheimer’s Disease (DIAD) Conference, an annual international meeting for those with inherited Alzheimer’s disease in the family, which was aptly called ‘Key to the Cure’. People like us are in a unique position to help scientists hunt for both biomarkers of the disease, and treatments that can be tested at the earliest stage, before symptoms have even begun. Seeing the close bonds being formed, and the advice and support shared by the families across the world was hugely uplifting.

If you’re deciding whether to get a genetic test, it’s worth remembering that it isn’t just dementia that’s a terminal diagnosis – life is. If your reasons for wanting to know are so that you can live your life to the full, why not book that holiday you always wanted, or run that marathon you always thought about anyway?

And for those, like me, who feel the need to open Pandora’s Box, but are still terrified of what will come out, know that others have been in the position and are ready to help.

For more support, go to www.raredementiasupport.org or to read about the genetics of dementia go to www.alzheimersresearchuk.org/dementia-information/genes-and-dementia/.