What’s the Life Expectancy of Someone with SYNGAP1

SCIENCE

JUNE 4, 2021

What’s the Life Expectancy of Someone with SYNGAP1‍

You’ve received the diagnosis: Your loved one has SYNGAP1, a rare genetic disorder caused by a variant on the SYNGAP1 gene. So many questions, so many emotions swirling around in your head. One question you’ll probably ask at some point is, “How long will my child/loved one live? What’s the life expectancy of someone with this disorder?”‍

‍What does the data tell us?

The first SYNGAP1 patient was diagnosed just twelve years ago in 2009, and so far, as documented in the most recent SynGAP Census, just over 750 people worldwide have gotten a SYNGAP1 diagnosis.The occurrence is probably much more prevalent, and numbers will grow with more testing, but what can we learn from the patient data available to date?

Although there aren’t yet extensive SynGAP-specific datasets to draw on, at least one large-scale study has been done on the life expectancy of disabled people in comparison to non-disabled. While the study did show that people with disabilities had a lower life expectancy (the gap was larger or smaller depending on the extent of the disabilities), it also clearly showed that people with disabilities often live well into adulthood.

In fact, here in the SynGAP community, we just celebrated the 65th birthday of one of our own. Happy birthday, Caren! (Make sure to watch the movie at syngap.fund/caren) And the literature holds a case report of a 31-year old with SYNGAP1.

Of course, SRF sponsors the Ciitizen Digital Natural History Study (which all families are encouraged to join free of charge) and we have 103 patients enrolled with Pathogenic or Likely Pathogenic diagnoses. This data includes a few adults. This does not tell us that few SYNGAP1 patients make it to adulthood, it tells us that too few adults are offered genetic testing.

A comprehensive SynGAP-specific article in GeneReviews states, “It is unknown if lifespan in SYNGAP1-ID is abnormal. One reported individual is alive at age 31 years, demonstrating that survival into adulthood is possible. Since many adults with disabilities have not undergone advanced genetic testing, it is likely that adults with this condition are underrecognized and underreported.”

Planning for what might be a long life ahead

It’s possible that the symptoms of SYNGAP1 may lead to a higher than usual rate of early death due to accident/injury (seizures, choking, aspiration, etc.). Indeed in the Vlaskamp 2019 Neurology “at the age of 33 patient 14, a 33-year-old nonverbal woman with a de novo SYNGAP1 nonsense mutation…died of aspiration pneumonia.”

But even with a painful case like this, it does appear that Syngapians can and do live many decades into adulthood.

So, although additional data and statistics are needed to answer the life expectancy question more definitively, with what we know so far, one answer is, “It could be long.” Remember, Caren survived COVID-19!

What does this mean for parents and family members? Plan! Long term planning is key, and it’s never too early to start. Special/supplemental needs trusts, finances, insurance, trustees, guardians, advocates, medical team, adult living situation … the list goes on and on.

‍Resources

Fortunately for those in the SRF community, you don’t have to go at this alone. Some starting points:

- Research! And you don’t have to go far. SRF has an ongoing series of blog posts dedicated to this very important topic. This blog on long term planning is a great place to start. As is this one. Both articles are written by Syngap moms and provide incredibly useful, practical information.

- Use the search feature on the SRF website to zero in on specific topics of interest to you. There’s a vast depth of knowledge here to explore.

- Share your knowledge: Have you done some planning already? Please complete this short survey if you’d like to share experiences.

Let’s learn from each other and support one another on the journey. And in the process, you can find some peace of mind in knowing that you’re doing all you can to protect and care for your Syngapian loved one.

Sources:

Vlaskamp, Danique R M et al. “SYNGAP1 encephalopathy: A distinctive generalized developmental and epileptic encephalopathy.” Neurology vol. 92,2 (2019): e96-e107. doi:10.1212/WNL.0000000000006729

Bahk, Jinwook et al. “The Life Expectancy Gap between Registered Disabled and Non-Disabled People in Korea from 2004 to 2017.” International journal of environmental research and public health vol. 16,14 2593. 20 Jul. 2019, doi:10.3390/ijerph16142593