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Autism is genetic

362 replies

jonesonscam · 17/09/2026 10:45

The National Autistic Society has just said something pretty significant: Autism is genetic. Not “possibly genetic”. Not “we’re not really sure what causes it”.

After reviewing 83 research papers, the NAS is now stating definitively that autism is genetic. You’re born autistic and you’re autistic for life. Most autistic people are autistic because of genes they inherited from their parents.

I think this matters enormously because for decades, autism has been surrounded by nonsense about vaccines, parenting, mothers doing something wrong, pregnancy, diet and a million other things.

It has left parents blaming themselves, and autistic people being told that something caused them to be autistic that could somehow have been prevented.

There isn't an “autism gene”. Thousands of genes are involved, and genetics is complicated. But the basic message is now remarkably clear: autism isn't something that happened to someone. It's something they were born with.

That matters because when we stop looking for something to blame, we can start looking at what actually matters: understanding autistic people, supporting them properly, and making a society that works for them.

This all feels like a pretty important shift.

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pointythings · 17/09/2026 10:47

I agree with you. But brace yourselves for the Mumsnet hordes who will be along to pile on with a load of ableist shite.

jonesonscam · 17/09/2026 10:49

pointythings · 17/09/2026 10:47

I agree with you. But brace yourselves for the Mumsnet hordes who will be along to pile on with a load of ableist shite.

Yes because facts don’t seem to be facts any more. Science isn’t science. Except it is. And it’s pretty conclusive on this.

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dairydebris · 17/09/2026 10:50

If it isn't caused by the environment then isnt it genetic by default anyway? I thought this was something we knew. Doesn't 'you were born with it' mean it's genetic anyway?

shellyleppard · 17/09/2026 10:51

Agree with the genetics. I'm sure I can trace autism in some form in my family going back two generations at least.
My eldest son has it too.

BunfightBetty · 17/09/2026 10:51

It’s important. But so too is Epigenetics and what it is in lifestyle and environment that causes genes to be expressed or not. That is where there is room to modify and sometimes ameliorate.

x2boys · 17/09/2026 10:52

It doesnt necessarily mean its inherited though .

Chexton · 17/09/2026 10:55

x2boys · 17/09/2026 10:52

It doesnt necessarily mean its inherited though .

Absolutely. All inherited conditions are genetic, but not all genetic conditions are inherited.

My lovely friend has wasted thousands trying to prove her son’s autism was caused by a car accident when he was a toddler. The truth is he was simply at an age where his autism started to show. I hope this shift will help her to focus on helping him rather than blaming others.

jonesonscam · 17/09/2026 10:56

Older parental age is associated with a small increase in the likelihood of autism. Parental age can also affect the occurrence of new genetic changes in an egg or sperm. In other words, even when people are talking about an “environmental” or parental factor, genetics can still be part of the mechanism.

The NAS is very clear: these factors have a much smaller effect than inherited genetics. There isn't one single “autism gene”. Thousands of genes can contribute.

Sometimes genetic changes are inherited; sometimes they arise spontaneously. It’s complicated — but the central point isn't:
“We don't know what causes autism.”
It's:
“We know autism is genetic. We just don't yet understand every part of the genetics.”

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OsfameronTanamoril · 17/09/2026 10:57

Didn't we know this already? Did they mention the age of the father being a contributing factor?

jonesonscam · 17/09/2026 10:58

Chexton · 17/09/2026 10:55

Absolutely. All inherited conditions are genetic, but not all genetic conditions are inherited.

My lovely friend has wasted thousands trying to prove her son’s autism was caused by a car accident when he was a toddler. The truth is he was simply at an age where his autism started to show. I hope this shift will help her to focus on helping him rather than blaming others.

Edited

One of the mums at my child’s special school thinks there was ‘something in the water’ locally because ‘How else did all these kids get autistic in the same place’

😬😬😬

OP posts:
jonesonscam · 17/09/2026 10:59

OsfameronTanamoril · 17/09/2026 10:57

Didn't we know this already? Did they mention the age of the father being a contributing factor?

Yes but nobody would state it definitely. The NAS have.

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TheGoddessFrigg · 17/09/2026 11:00

Anyone who met my father and his mother would have had suspicions of this!

Funnywonder · 17/09/2026 11:00

My eldest was diagnosed with ASD at 17yo after a long, long wait. Closely followed by ADHD. In all honesty, he is ‘every turn of me’ as we like to say here in NI, meaning we are very alike. My partner also very likely has ASD. Many (or most) of our son’s autistic traits have seemed ‘normal’ to us because they were part of us too. Our youngest is now awaiting assessment. Many members of both our wider family circles have an ASD diagnosis. So, using my small study of just two joined families, I am not even slightly surprised by this!

ElephantInTheRooom · 17/09/2026 11:00

I have 4 autistic kids and neither me or their father are autistic, and no one else in our family is (on both sides.) So I'm not convinced.

OsfameronTanamoril · 17/09/2026 11:00

I don't think it will convince the anti-vaxxers.

UnpopularOpinionsIWouldUsuallyKeepToMyself · 17/09/2026 11:03

ElephantInTheRooom · 17/09/2026 11:00

I have 4 autistic kids and neither me or their father are autistic, and no one else in our family is (on both sides.) So I'm not convinced.

That's the difference between genetic and hereditary.

UnpopularOpinionsIWouldUsuallyKeepToMyself · 17/09/2026 11:04

Many (or most) of our son’s autistic traits have seemed ‘normal’ to us because they were part of us too

This really hits home, you've verbalised something I have only latterly come to realise about our famliy.

BeigeCardiganOfDoom · 17/09/2026 11:06

You should alter your responses so they’re not so obviously cut and pasted from AI.

x2boys · 17/09/2026 11:06

ElephantInTheRooom · 17/09/2026 11:00

I have 4 autistic kids and neither me or their father are autistic, and no one else in our family is (on both sides.) So I'm not convinced.

That doesnt mean its not genetic
My son has an underlying chromosome deletion thats thought to be reason for his autism and learning disabillties it wasent inherited ftom either me or his Dad it was De novo in him and neither me or my Dh are autistic

HorseandHeron · 17/09/2026 11:06

Funnywonder · 17/09/2026 11:00

My eldest was diagnosed with ASD at 17yo after a long, long wait. Closely followed by ADHD. In all honesty, he is ‘every turn of me’ as we like to say here in NI, meaning we are very alike. My partner also very likely has ASD. Many (or most) of our son’s autistic traits have seemed ‘normal’ to us because they were part of us too. Our youngest is now awaiting assessment. Many members of both our wider family circles have an ASD diagnosis. So, using my small study of just two joined families, I am not even slightly surprised by this!

This is so true. DS wasn't diagnosed until he was twelve and Dh and i were astonished. Because we are both neurodiverse, his behaviour was normal to us.

Maybeshesbornwithitmaybeitssertraline · 17/09/2026 11:09

ElephantInTheRooom · 17/09/2026 11:00

I have 4 autistic kids and neither me or their father are autistic, and no one else in our family is (on both sides.) So I'm not convinced.

I have 4 autistic dc too. My dh is also autistic and both our families are full of autistic people though.

DramaAlpaca · 17/09/2026 11:12

UnpopularOpinionsIWouldUsuallyKeepToMyself · 17/09/2026 11:04

Many (or most) of our son’s autistic traits have seemed ‘normal’ to us because they were part of us too

This really hits home, you've verbalised something I have only latterly come to realise about our famliy.

Same here, it really hits home to me as well.

Conniebygaslight · 17/09/2026 11:16

I also wonder if there is perhaps another condition that presents similarly to ASC that is caused by modern life and this is what the increase is.

cupfinalchaos · 17/09/2026 11:17

I’m hardly surprised. Most autistic people I know have several in their family, never seems to be just them.

tealandteal · 17/09/2026 11:19

My oldest received his diagnosis yesterday. There is no diagnosed autism in the family but if some of them were children now they would almost certainly be diagnosed. Let’s not forget that not so many years ago many nonverbal or more complex/severe autistic or other neurodivergent children would have been kept completely at home or perhaps lived in an institution, so we do see more autistic children out and about. Aunt Betty with her collection of horse plates or cat figurines was just quirky.

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