Inherited motor neurone disease (MND)
Deciding whether to have pre-symptomatic genetic testing: Reasons for wanting to know
Pre-symptomatic genetic testing is available to some people who do not currently have symptoms of MND but have an increased chance of developing it in the future. This section covers:
- Coming to a decision on pre-symptomatic genetic testing for inherited MND
- Deciding to have pre-symptomatic genetic testing for inherited MND- reasons for wanting to know
Pre-symptomatic genetic testing (sometimes called ‘predictive testing’) is generally only offered where a genetic variant linked to inherited MND has already been identified in an affected relative. It allows people without symptoms to find out if they have inherited this particular gene variant. Deciding whether to have pre-symptomatic genetic testing is an individual choice, with many factors involved.
Coming to a decision on pre-symptomatic genetic testing for inherited MND
The people we spoke to had different experiences of deciding whether to have pre-symptomatic genetic testing. Some people described their decision as quick and self-evident; they knew almost immediately what they wanted to do. This included people who decided to pursue testing, such as Jade, who “wanted the test 100% from the minute I knew”, and people who did not want to find out their genetic status, like Richard who made the decision “pretty much instantaneously”.
Georgia had the genetic test shortly after losing her mum and aunt to MND. Looking back, she feels she didn’t think too much about the test, “I think maybe I was so numb from everything that I didn’t even think too much into it… it’s weird, but I just knew that I wanted to know”.
Other people we interviewed weighed up the possible benefits and drawbacks of pre-symptomatic genetic testing for inherited MND. Anthony considered the potential impact of finding out the result versus not knowing, and wrote a pros and cons list. His list of reasons to have the test was a lot longer and after discussing it with his wife he knew quite quickly that he wanted to go ahead.
Calum spent around 18 months considering what he would get out of pre-symptomatic genetic testing. Although he had concerns, he felt these were outweighed by the benefits of knowing.
Calum spent around 18 months considering what he would get out of pre-symptomatic genetic testing. Although he had concerns, he felt these were outweighed by the benefits of knowing.
From the point that my father, I found out my father’s diagnosis I had for that entire year and a half, whatever it was, decided that I should get tested, but I was weighing up whether it was worth it, and you’re constantly weighing it up every week, like, “Why, what do I get out of it? What’s the risk of knowing?” It just came to a point in August where I was like, “Look, I need to know”, like even if there are like massive cons to knowing I think the pros… Like I did, I like weighed up whether being able to plan for something horrible happening in your life is better than having it randomly happen and it outweighed it massively and I just decided there and then to do it.
I was at a time in my life where I felt you know, I’m 24, 26, and, no, I was 25 at the time, yeah, I was 25, and I was thinking, “If I can have 25 years of knowing and living my life normally, happy and comfortable with that, great”, rather than 25 years ahead of me thinking, “Do I have it, do I have it? Do I not”, you know, I think it would’ve been worse. So that’s probably what weighed up my decision.
It is important to note that people’s feelings on pre-symptomatic testing often changed with time and with shifting circumstances. Sam described how over time, they got used to the idea of having a 50% chance of having inherited the gene variant linked to inherited MND, and more recently feel it is “worth the risk” of taking the test. Maggie had an immediate feeling that she was more comfortable not finding out if she had inherited the C9orf72 genetic variant, yet over the next two years her views changed and she decided it would be worth knowing. Another person we spoke to believed that a relative would not have approved of her having the test, yet after they died, she felt “able to make that decision for myself”.
Deciding to have pre-symptomatic genetic testing for inherited MND- reasons for wanting to know
People who had had the pre-symptomatic genetic test spoke of a range of motivations and considerations; most people we interviewed mentioned several reasons which influenced their decision.
Some people found it difficult to live with the uncertainty of knowing that they could have inherited a gene variant associated with inherited MND. Calum tried to put it to the back of his mind and live his life, but he always had a feeling of ambiguity and uncertainty. He believed that spending the next 25 years questioning whether he had inherited it would be worse than knowing he did. Other people described feeling in “limbo”. Jade described herself as someone who likes to “know all the facts” and “get on with it”. Lizbeth wanted a sense of certainty and control. Lillian pointed out that she was already worried by knowing she had a 50% chance of having inherited the C9orf72 gene variant from her father.
Another difficulty of living with uncertainty was worrying about possible symptoms. Maggie had experienced periods where she had convinced herself she had symptoms, and started to question whether she could be worrying unnecessarily. For Anthony, the choice around testing was itself a source of stress.
Anthony felt that having the pre-symptomatic genetic test would leave him “better off emotionally”. He wanted to move past the decision and on to the next one.
Anthony felt that having the pre-symptomatic genetic test would leave him “better off emotionally”. He wanted to move past the decision and on to the next one.
So when we found out it was genetic we talked about it and we were like, ‘We want to know,’ basically. My wife and I wanted to know, and it’s around the things we talked about … I’m better off knowing emotionally, from a probability point of view. To do the research, to plan ahead, to be able to know we need to tell the kids… I mean, the stage of life where, yeah, maybe we’re emotionally more equipped to be able to make that decision. I don’t know, depends on the stage of life you’re at. And I suppose, the other school of thought is if you don’t know then it doesn’t impact you. But for me, I still think it would impact you even if you didn’t find out, because you’d be constantly, ‘Should I get tested? Should I get tested? Should I get tested?’ and it’s… I don’t know.
For me, it’s better to know and just move past that decision and then on to the next one. And that decision itself causes a level of emotional stress, you know? And even when you get tested, you do have a 50% chance of it being lifted off your shoulders completely, but the other 50%, then you move on to the next course, basically.
As Anthony mentioned, the 50% chance of receiving a negative result was an important factor in having the test. Jade and Georgia Z both had a sense that they would receive a negative result; Jade wanted to find out so she could “put it to bed”. Georgia Z described her motivations.
An “instinct” that she would receive a negative result pushed Georgia Z to have the pre-symptomatic genetic test. Having lost her mum and aunt to MND, she thought “what am I really losing?”
An “instinct” that she would receive a negative result pushed Georgia Z to have the pre-symptomatic genetic test. Having lost her mum and aunt to MND, she thought “what am I really losing?”
So, I guess although me and my partner weren’t ready for a baby now, there is kind of in the back of your mind, because you’d have to go through the IVF process if you wanted to avoid the gene continuing.
So I guess that played a bit of a part just for me; I wanted to be a bit prepared. But as well it was just, honestly, it was just curiosity. I’m a very curious person and I actually had an instinct that I didn’t have it from the start, and I don’t know if that - I mean it’s only instinct - but that actually pushed me. I was like, I don’t know, I feel like I’m more my dad. Like it was such a weird, I don’t know, I just had a gut instinct, and I think maybe that’s why I didn’t feel so fearful and I just went through with it. If I’m honest, it’s taken two of the most strongest women in our family, so what’s the loss, what am I really losing? I lived for my mum so, and you’ve taken her so it is what it is really, whatever my result is.
For some people we spoke to, having genetic testing was about being prepared and planning ahead. This was often related to having children. Calum and Kelly both wanted children in the future and personally felt they did not want to risk passing on a gene variant linked to inherited MND, or for their children to go through the situation they had of knowing they could have an increased chance of developing MND.
Calum feels grateful to have learnt about reproductive options to prevent his future children from going through what he has gone through. He sees stopping the disease as a “no brainer”.
Calum feels grateful to have learnt about reproductive options to prevent his future children from going through what he has gone through. He sees stopping the disease as a “no brainer”.
I didn’t want to continue a path down a life and build a life for me that could be destroyed by motor neurone disease. I’d much rather be able to build a family and protect it potentially from motor neurone disease than not, and it was purely the fact of having children, I did not want to have children that would lose their father and then find out that they could be at risk of being, suffering from the same disease, that is just horrendous.
So, I think I decided at that point, because I didn’t know you could prevent it, I had decided at that point that I would find out if I had it, I would then not have children, and if I didn’t have it, I would just live my life normal. Then I found out that you can have this special IVF, I think it’s RIVF, and that’ll take, solve my problem. It doesn’t solve your problem because you know, you only get one child out of it and you have to pay for like the IVF for any other children and it takes a year to go through the process and things like that, but you are still able to have a family.
I think it’s a no-brainer to, if you can go through a process where you can filter, your partner and your child from being vulnerable to something that could devastate them immediately or later in life it’s, there’s no choice really. It’s a weird case of eugenics I think in how you can test a population for something and making decisions around it, but it makes sense and it, if it does one thing to stop people passing on a horrible gene and makes society better then it, I think it should be worth it really.
It definitely brought up some eugenic sort of questions in my head, but we won’t go down that road sort of thing [laughs]. It’s just a weird thing because it, it’s such a massive thing to be able to control whether someone’s born with something or not, and I think it’s just weird to think that I, as a parent, will have a 50% like decision in that, that life being born and how it’s born, it’s just weird. But it was a massive part of why I wanted to get tested and I was really grateful for knowing that those are the options because I didn’t know they were the options, and if I hadn’t gone through the counselling, I would never have known that.
For Harriet, who had one child when she found out about inherited MND in her family, having the pre-symptomatic genetic test was a “no-brainer”; “we weren’t prepared to continue with our family until we knew the outcome”. Harriet felt it was important to know whether she carried the C9orf72 gene variant to inform decisions on reproductive options, including genetic testing before or during pregnancy.
Having pre-symptomatic genetic testing was also about having concrete information for existing children. Lizbeth and Jade wanted their children to be able to make informed decisions when it came to thinking about having families of their own. As Lizbeth said, “they’ve got far more solid information than I ever did, and I wanted that for them”. One reason Anthony wanted to have genetic testing was to find out if his children could have inherited the C9orf72 gene variant. He can now plan how to talk to them about inherited MND.
For Anthony, planning ahead was also about trying to live a better life in the present, as well as getting involved in things like fundraising. Individuals we spoke to wanted pre-symptomatic testing to inform choices around putting things in place for the future, such as insurance. Other people pointed out that they could do these things anyway, without knowing their genetic status.
People we spoke to also felt that having the pre-symptomatic genetic test would make them better prepared if they were to develop symptoms. Jade hoped this could lead to a faster diagnosis. If a treatment was available, she might be able to have it more quickly.
If she were to develop symptoms, Maggie hoped that being diagnosed early would enable her to join a clinical trial. This was one reason why she changed her mind about having pre-symptomatic genetic testing.
If she were to develop symptoms, Maggie hoped that being diagnosed early would enable her to join a clinical trial. This was one reason why she changed her mind about having pre-symptomatic genetic testing.
Initially when I first started to think about it, I thought “No”. As I said right at the beginning, I don’t want to know, I just thought, “Well, there’s nothing I can do about it, I just don’t need to know”. And I think because in a way I was looking for symptoms, waiting for symptoms to develop, waiting to find that something was wrong, you can kind of frighten yourself into thinking that something’s wrong when it isn’t, and then I thought well, “I would love to know that I haven’t got it” but I couldn’t know that I hadn’t got it without then knowing that I had. Because you could say to somebody, “Okay, fine, test me, let me know if I haven’t got it”, and then you don’t hear from them, you know that you have. So, you can’t… And then you can’t unknow, once you know, you can’t unknow. So, I thought, “No, I’ll leave it”. But then as time went on I was thinking, “Oh if I haven’t got it why am I worrying?” and if I’ve managed to convince myself several times that I have got it, I might be convincing myself unnecessarily.
And then there was this whole thing about trials. John, my brother, nearly went on a trial but then his condition deteriorated too far, and they couldn’t, couldn’t take him on. I thought, “Well, if I knew in advance that I had the defective gene, and a trial came up when I was having early symptoms, I would possibly have a better chance of getting onto a trial.” So, I felt that being forewarned might be a good thing. And so I went to the GP and discussed all these things with her and she said, “You’ve answered all my questions before I asked them” [laughs]. But she said, “Yeah, you seem to have thought it through”, and it’s taken about two years to come to the idea that actually I just think I do want to know.
Taking part in research was also important for Anthony. He decided to have genetic testing with a plan to “throw myself into as much research as I could” if he received a positive result.
Even people who had had pre-symptomatic testing had reservations and concerns. Calum initially worried that having a positive genetic test result on his medical history could impact his ability to secure insurance and a mortgage or limit his career. Although it is important to be honest when asked questions by insurance companies about one’s own or a family member’s medical history, Genetic Alliance UK advises that people in the UK do not have to disclose predictive test results for inherited MND.
At first, Maggie felt more comfortable with knowing it was “50:50” whether she had inherited the C9orf72 gene variant from her mother and, before finding out one way or the other, thinking of her children as having an overall 25% chance of having inherited the gene variant (50% x 50%). She later changed her mind.
Although people often felt sure of their choice to have the test by the time they started the genetic counselling process, this was not the case for everyone. Sam felt that they would be able to live a “happy” and “fulfilling” life if they tested positive, but nonetheless questioned whether their decision might change after having genetic counselling.
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