Autism mutations drive neurodevelopmental pathology

(science.org)

62 points | by slantedview 3 hours ago

2 comments

  • SubiculumCode 1 hour ago
    autism researcher here. I have not yet read this study. It will not be the kind of paper that many, including myself, can read quickly and understand. Autism is a multi-disciplined science, so there is a lot to understand. However, my initial sense from reading the abstract is that this paper might be a really really big deal and incredible new resource.

    General problem statement: Many different genetic variants are associated with autism, some strongly, most very weakly. Many have suspected that this plethora of genetic variants might converge onto a smaller set of biological pathways affecting neurodevelopment in ways that results in an autism phenotype or phenotypes. This has been our hope, because the alternative scares the hell out of a scientist. The saying goes that if you met one person with autism, you've met one person with autism...meaning there is a ton of heterogeneity within the autism spectrum, even if a certain set of core autism symptoms are displayed. So there was a existential crisis that there is no "autism", just a billion autisms, where your sample size is always N=1. By demonstrating evidence that many variants converge on the same biological pathways, there is hope that understanding autism is tractable.

    • roughly 1 hour ago
      Out of curiosity, what leads us to treat ASD as an actual single disorder, as opposed to a billion different individual neurological profiles?

      I'd expect one of the things that makes this difficult, too, is that there's a missing component of the "machine" - the genetics affect the pathways, which affect (maybe?) things like signal propagation or network regulation in the brain, but the actual effect of that is on the patient's experience of consciousness, and it's difficult for someone to get more than N=1 of those via commonly accepted legal methods - otherwise, we're all just looking at the outside of the box and saying "huh, this box acts differently than that box, weird."

      • SubiculumCode 1 hour ago
        A lot of the behaviors by which autism is diagnosed (social communication, repetitive behaviors and restricted interests) are fairly high-level behaviors, dependent on a lot of cognitive/neural machinery beneath it. There is an idea out there that convergent behaviors that allow consistent diagnosis depends on this, as the resulting behaviors might results from differences in many different underlying processes, but the result at the higher level can be measured the same.

        Analogy: Two programs can produce nearly identical behavior at the UI level, but be implemented very differently. Diagnosis operates partly at the "interface" level, but what happens underneath can differ greatly.

        • roughly 20 minutes ago
          Ok, that makes sense - so ASD is basically that we’ve noticed some prototypical behaviors, which is where the grouping comes from, but it’s possible what we’re seeing is sort of the “carcinization” of mental operating modes - many different pathways into the same output point, which is why the genetic search has been so difficult - that right enough for a non-scientist?

          What I know of the brain is that it’s basically a chaos machine - a ton of activity that’s just on the edge of a cascade, a bunch of feedback loops, a bunch of emergent behavior, and it’s kind of impressive we function at all to begin with, so it’s not surprising there’s so many ways to perturb the output behavior.

        • sublinear 1 hour ago
          Is high-level behavior the only criteria for diagnosis?

          I think the majority of the public would like to better understand how we came into this position. There's nothing wrong with the topic of autism as research, but it's been a political football for so long that there are many reasonable doubts about methodology, diagnosis, and relevance to everyday healthcare. I understand there may be complications with some patients that require medical diagnosis and intervention, but does that not imply there should be a much more meaningful label on those cases than just the broad umbrella term of "autism"?

          On one extreme, we have people thinking they're autistic when they're actually just awkward and inexperienced in life. On the other, we have people with epilepsy who prefer the label "autism" even though they're merely correlated. Something is wrong here. Not with the science, but the discussion.

      • imzadi 1 hour ago
        I feel like your initial question can be applied to a lot of things. For instance, Elher Danlos Syndrome has 13 variations depending on which gene is mutated. This include 11 known mutations and 2 catch-all categories for variations where we haven't yet found the mutation. Why are all these mutations under the same disease when they have such a range of symptoms? My guess is that it is because they were all lumped together before we had the language to talk about them as separate things or the technology to identify the causes. Going back and saying oh all these people don't have ASD or EDS or whatever but this specific thing that we have now identified might cause some disruption is research and awareness.
        • roughly 14 minutes ago
          From what I know of cell biology (read: committed dilettante), the notion that one gene does X is rarely correct. The way to think about genes and the proteins they encode for is less “blue eyes” and more “metric socket wrench #5” - the protein is a tool, and lacking that tool means any operation that requires that tool isn’t going to function as normal, which is why you see such weird disparate effects from mutations and also multiple genetic pathways to the same pathology.

          Also nature is absurdly cavalier about using whatever it’s got at hand, so it’s not so much “metric socket wrench #5” as “the pry-bar/hammer/thing we use to hold the hood open” that gets fucky when the genes go wrong.

      • Alex3917 1 hour ago
        > what leads us to treat ASD as an actual single disorder, as opposed to a billion different individual neurological profiles?

        We already do treat it as the latter. The medical definition of autism is basically just any neurodevelopmental disorder that isn’t ADHD.

        • kulahan 30 minutes ago
          "Why don't we treat it as many disorders instead of just calling everything autism?"

          "we do, autism is everything that isn't ADHD"

          ...what? I must be stroking out, but I have no idea what point you're making here...?

          • Alex3917 17 minutes ago
            My point is that autism is already treated by the medical system as many disorders and not as a single thing. The reason they all share a common label is for political reasons, where it makes sense to group them together. But the actual medical system does not treat them as having anything in common, let alone as being homogeneous.
        • reubn 1 hour ago
          What a ridiculous take.
    • hbcondo714 54 minutes ago
      @SubiculumCode, thanks for this comment and helping us understand better. Is there by chance a way to contact you about your research & expertise or would you mind contacting me using my profile info? I built https://behavior.today and would love to connect on this topic. Thanks!
    • XCSme 1 hour ago
      As a potential autist, I think everyone is autistic in one way or another (which would make everyone neuroytpical, lol).

      In the end, maybe we are just all unique individuals with our character sliders set in various forms.

      • flatline 41 minutes ago
        This line of thinking diminishes the real struggles autistic people face. Not everyone is autistic, and it's not just a quirky set of traits. I do believe society could be better arranged for people who for whatever reason don't conform to the overculture norms, so we could talk about disability along the axis of how society privileges or disadvantages certain individuals.

        The concern is that autism as a rigorous category may be useless, but that doesn't mean that autistic people are suddenly neurotypical -- a term that is more politically than scientifically oriented. People who are not autistic broadly are allistic, to be precise with language. They may be neurodivergent in other ways.

        • XCSme 31 minutes ago
          I said that if everyone is neurodivergent, then no one is.

          Same with IQ, if everyone is 150IQ, then everyone is still 100IQ, as per the definition, so "normal".

          Divergence can only be mentioned when talking a base value to diverge from. What if neurotypicals are actually the neurodivergent ones?

          • hoppp 26 minutes ago
            Typicals are the neurotype that reproduces fastest, that's it.
        • XCSme 33 minutes ago
          But different autistic people struggle with different things, in different ways.

          What's even the point of having a general diagnosis umbrella, if the symptoms are different?

          • autoexec 5 minutes ago
            > But different autistic people struggle with different things, in different ways.

            Different asthmatic people struggle with different things, in different ways too, but it's useful to have a general diagnosis umbrella to cover those who have asthma even though symptoms and effective treatments may vary.

            Work in ongoing to get better defined categories for autistic people, but for now at least we've got a category for people that match a broad set of traits/symptoms/challenges to work from.

          • flatline 20 minutes ago
            General doesn’t mean it applies to literally everyone. If autism turns out to be a specific condition that is e.g. the result of abnormal neuron pruning during early development, it could have a wide array of symptoms, but that understanding may someday lead to genetic treatments for sever cases, better early childhood interventions, etc.

            I do think that the current ASD umbrella as written in the DSM is so broad as to seem nearly meaningless when take in isolation. It’s not meant to be in isolation however, it’s defined first and foremost as a disorder, so the symptoms need to cross some threshold of tolerable. It’s also associated with a growing body of research as to how nervous system development can cause related clusters of symptoms.

            Is autism as we understand it scientifically accurate? Probably about as much as anything in the social sciences. It does have some predictive power. If you meet the diagnostic criteria for autism you are likely to have certain comorbidities for example. Having certain autistic traits are good predictors of certain outcomes later in life. And we do have better therapies especially for young people than we have in the past.

            The fact that people can have non-overlapping clusters of traits and still be autistic does seem problematic. It may not be the right model. Just my $.02, I’m not the autism researcher in this convo, but I am autistic :)

    • throw939ii44 1 hour ago
      Genetics does not explain steep raise in last a few decades.

      Anyway, we do not really know what is causing it, have no real idea what it even is. But we must apply occam's razor very very quickly!

      • SubiculumCode 1 hour ago
        First, and foremost, the rise in autism rates is due to more sensitive instruments, a broadening of some inclusion criteria between DSM 4 and 5, more awareness of autism, less stigma associated with autism, services attached to autism diagnosis. I believe current research suggests these don't account for all the rise, but does account for most of it.

        If I were to include additional biological possibilities, I'd include: a) birth control -> waiting to have children until a later age, more de novo mutations due to age. b) assortive mating, since some careers tend to attract those on the within and on the edges of the spectrum., c) perhaps controversially, and with the very little research on the subject, endocrine disruption from plastic waste exposures.

        • longhaul 5 minutes ago
          @SubiculumCode - replying as you are a researcher in this field. There is an increase in profound autism globally (I think this is the new naming to differentiate severe autism) which isn’t explained by sensitive instruments or inclusion criteria. You just don’t need them to identify profound autism, it is that obvious. Affected people need caregivers for life also causing severe mental and financial stress. It will only help your research to investigate this increase which perhaps will lead to medical breakthroughs.
        • throw939ii44 51 minutes ago
          Severe autism is on raise as well, and that has stable diagnoses over several years. Plus general cognitive decline in last a few decades is also documented.

          Is it politically correct to write about later stage pregnancies? It would be insta ban only a few years ago.

          Perhaps soon we will be able to openly discus something else, that may cause endocrine disruption, not just plastics!

      • john_strinlai 1 hour ago
        >Genetics does not explain steep raise in last a few decades.

        as we built better telescopes, we found more stars

      • jasonpeacock 1 hour ago
        The steep rise in the last few decades is primarily due to increased awareness and expanded definition/diagnoses.
    • s1artibartfast 1 hour ago
      When autism is discussed as a culmination of denovo mutations, one thing that I dont understand is how this is reconciled with the history of the species.

      It seems there is a high rate of mutations, making the non-mutant ensemble incredibly fragile. How did this work in the past? Was there significant selection against mutant varieties?

      • SubiculumCode 1 hour ago
        Genetic contributors to autism include:

        1. common variants. Common variants are genetic variants weakly associated with autism that we all have to some degree or another, and that only result in autism given a sufficient number of them are found in a person..or at least that's a common idea and pretty well supported. These variants are inherited.

        2. rare de novo variants: These are spontaneous genetic variants that the parents did not have, but there was a mutation during production of sperm, for example. Many times, rare de novo variants that occur in highly conserved genes cause tremendous neurodevelopmental problems, spanning death often prenatally, other conditions, and for, autism, most frequently with severe intellectual disability.

        Common variants are heritable and common, and are part of the normal spectrum. Only with a very large load do these result in the severest conditions, I think, like intellectual disability.

        Occurrence of rare de novo variants are associated with things like age of father (older, less reliable production of sperm without genetic mutations), pesticide exposures, etc.

        There is also a real immune factor involved, as well as environmental exposures, which can interact with genes.

        • s1artibartfast 39 minutes ago
          Is there an understanding of the relative prevalence of each type in modern society? Thinking about changing rates of diagnosis, with common circulating variants, it seems like changes to detection and classification would be the only explanation for rate change.
      • 1attice 1 hour ago
        That's a good question with a neat answer: assortive mating can amplify a randomly occurring gene by sexual selection. Read on for the details.

        Suppose that there was a gene that made you more likely to be good at white collar thinkwork. You meet your partner at a professional event and have a baby. The baby now has between zero and two copies of the gene. And depending on gene dominance, the probability of at least repeating the ratio of the previous generation is like 75% IIRC.

        Repeat, and fold back in. Next generation, you have a couple folks with both mutations, who exhibit an even stronger affinity for quiet thoughtful work (and people). Their kids will have a 100% chance of carrying at least one copy, right? The numbers for the third gen will be even higher.

        This is all massively simplified but yeah. Mendel has the answers. The picture is even clearer if you suppose multiple genes whose effects stack, which appears to be the case with the ol 'tism.

        And, finally, there is the lived experience of why this happens so much. Speaking as someone on the spec, I could never imagine life partnership with an allistic person, nor can I imagine such a person putting up with my deficiencies and quirks. Moreover, quite literally all my friends are also autspec and would never interface with someone who isn't. So I believe ASD is strongly selected for by people with ASD.

        But given the volumes I'd expect we are in the hockey stick armpit of an exponential curve. Like HIV bubbling away in 1950s Africa long before we even had a name for the condition, nineteenth century colonial industrialism probably quietly worked up a stock of the relevant mutations, and the mutants found each other in the grand blender of the 20th century's upheavals.

        As it were, silicon valley is one of the precipitants of sex, war, and intellect.

    • gignico 1 hour ago
      I thought the US government had just decided that the cause of autism was vaccines </sarcasm>
  • kayo_20211030 2 hours ago
    I'm interested - for reasons. Does anyone have a sense of what this study means in a practical or actionable sense?

    In toto, the conclusion of the paper:

    > Together, these findings define a dual-layered model of molecular convergence in ASD: convergence through shared interaction networks in the wild-type state and convergence through recurrent functional consequences of interaction rewiring in the mutant state. More broadly, this work establishes a scalable framework for systematic interrogation of the autism proteome, enables prioritization of druggable protein interfaces, and provides a rational foundation for precision therapeutic strategies aimed at restoring neurodevelopmental trajectories.

    I have no grounding here. Does anyone want to have a go at teasing the meaning out?

    • randomImmigrant 1 hour ago
      Here’s how I’m thinking about it (still digging into the details): across genomics, it’s become clear few traits have clear traceability to a few loci in the genome.

      Instead, evidence has been growing that epistasis, the nonlinear interaction between genes and other genomic regions, predominates in explanations of most phenotypes.

      What this paper does is show where upstream of the genome various combinations of mutations can interact to cause damage during development, thus leading to the phenotype. Rather than correcting a particular mutation, or targeting drugs to their protein products, we may find downstream protein-protein interactions that are strong drivers of the phenotype, and hopefully find ways to prevent/reverse these effects.

    • AndrewDucker 1 hour ago
      Nothing yet. This is incredibly preliminary, with lots of this being tested in frogs.

      It hopefully gives hints which will be tested,better understood, and show actual mechanisms in humans. But probably not for years.

      • klipt 1 hour ago
        Dr: I have good news and bad news

        Patient: What's the good news?

        Dr: We have a two step treatment to improve your social-emotional life.

        Patient: What's the bad news?

        Dr: The first step is, we have to turn you into a frog...

    • slantedview 1 hour ago
      There's a CNN article that has some expert quotes for context, but isn't quite as in depth as the study itself: https://archive.ph/yBiM8
    • rickydroll 2 hours ago
      I interpret it as they think they can find treatments that will course-correct the development of a child, but they're not saying anything about fixing something that's already broken.
      • Muromec 1 hour ago
        I for once enjoy the glitches in my signal mixing module, don't want nothing to fix there.
      • forestrywat 1 hour ago
        What do you mean "broken"? Autistic folks are not broken.
        • rickydroll 24 minutes ago
          I live with a child who spends entire days with videos on his tablet. We can't take him anywhere because if the trip differs from what we told him (trip duration or locations), we have to abort the trip to prevent a meltdown. His inflexibility means he can't hold a job or go to school or training. He can't do household chores without prompting and handholding. He will never live alone or have anything resembling a functional life. We have to make plans for how he will live after his mother and father die. We have to make space for his meltdowns that seem to come out of nowhere.

          His mother nearly bankrupted herself paying for private school for kids on the spectrum. His parents sued the local school system because they didn't have any teachers who had any skill with autistic children. couldn't protect him from bullying and couldn't or wouldn't follow the IEP. (Note: this is one of those events that ruin retirement plans). The state claims to have resources for my partner and her child, but when they try to get help, the state says it didn't realize she would need that much help.

          Then there is the never-ending struggle to get appropriate psychiatric and psychological help for him, and if you think it's hard to find a psychiatrist for ordinary mental illnesses, finding someone who knows how to deal with kids on the spectrum is almost impossible.

          His disability has had a negative impact on my relationship with his mother. As she has to make room for her child's emotional outbursts, I make room for my partner's angst about having a child who will never function on his own. There is a big loss of day-to-day intimacy because you never know when you will have to put up an emotional barrier against his behavior.

          yea, in my eyes, that counts as broken

        • djaro 1 hour ago
          Autism is a disability. The function of the brain to normally process social cues is broken. In the same way someone who is blind has broken vision, someone in a wheelchair has broken legs, and someone with ADHD has broken executive function.

          This isnt a moral judgement, theres nothing wrong with being disabled, but it remaims a disability that many people struggle due to.

          • hoppp 33 minutes ago
            The disability exists when compared to neurotypicals but does not necessarily exist when compared to other autists.

            As a comparison, if you put a bonobo with chimps the bonobo will be severely disabled socially, but it won't be when compared to other bonobos.

            The fact that autists can communicate with each other does not fit typical models of disability. A blind person should be blind to another blind person.

        • mapontosevenths 54 minutes ago
          Some autistic people have to wear helmets and spend all day rocking back and forth eating anything they find in the carpet. The are unable to care for themselves and depend fully on others.

          These people are not operating within the nominal range of human behavior that might be classified as "functional."

          Only 20-30% of adult Autistics can even hold a job. Not a 'good' job, mind you, ANY job.

        • nick__m 59 minutes ago
          There a point on the spectrum where someone cannot function without supervised housing and another one where you have non verbal autistic folks.

          But I agree broken is not the right word for those poor folks because they were never functional to begin with!

        • raducu 1 hour ago
          Nobody said they were, but broken in terms of neurotypical circuitry, yes
      • kelseyfrog 1 hour ago
        Brave to say on one of the most autistic web forums that autistic people have something that's broken :|
        • SubiculumCode 1 hour ago
          Autism is a spectrum. Neurodiversity within and outside of autism is both intrinsically valuable and extrinsically valuable to society. However, not all phenotypes of autism should be viewed as neurodiversity, but as harmful. There is only so much that society can do to make severe intellectual impairments less disabling without identifying a cure for the intellectual impairment. The debate between medical versus disability models, neurodiversity versus pathology, inevitably gets pushed by those that want to classify everything into clean essentialist boxes, but that, I do not believe, is a helpful way to view the world. Not every condition is a pathology, nor is every condition benign if only society would do more to make it less disabling.
        • djaro 1 hour ago
          I mean, it's classified as a disability for a good reason.

          I would guess that even if this platform has more autistic people due to being tech focused, autistic tech nerds and programmers are on the extreme end of high-functioning. Many low-functioning autistic people will never be able to have a job or live by themselves.

          This is the same issue as high-functioning ADHD'ers saying "ADHD is my superpower", meanwhile people with severe ADHD do significantly worse than the general population in basically any metric, up to having a lower life expectancy.

          This isnt to say its morally bad, theres nothing wrong with being autistic or having ADHD, but it is a disability. Just like someone who's deaf can live a totally happy life but still be disabled because they are not able to hear, someone with autism is disabled because they are not able to process social cues at the same speed, even if they are a great person and have a good life.

          • forestrywat 1 hour ago
            "Have a disability" and "broken" are not synonyms.

            There's no judgement or moralizing in having a disability. Autism and ADHD like you mentioned are disabilities.

            But the people who have them are not broken. Having a disability means some part of your life is more difficult. But that's very very different from you as a person are broken.

            For example, if you can fix the environment and the person can now function equally to someone without a disability, then maybe it's the environment that's broken. If you can fix the social expectation and suddenly the person can function equally, then maybe the society is broken. Even if you cannot accommodate the person's needs, insinuating they are broken is not a great framing -- it creates a sense of pity rather than constructively looking at means to support them.

            • hoppp 30 minutes ago
              What is strange about the disability is when neurotypicals attack autists. It takes less then 1 second for the negative bias to trigger.

              If you see a person without legs, do you tell him he is a piece of shit because he can't run? So why harass autistic people?

              • switchbak 17 minutes ago
                That's just people though, if you walk around with a scar on your head you'll see lots of knee-jerk immediate reactions. Some people are able to mediate those initial reactions and be kind, others just go with it and treat people poorly. Yes - some people are a'holes, and treat those without legs poorly.

                The same is true of basically anyone that doesn't fit into what you typically see - there's always some people that will treat them poorly. It's unfortunate, but was probably adaptive during our evolution, and something we just have to deal with today.

            • nick__m 56 minutes ago
              What else but pity should I feel toward non verbal autistic people?
          • seanhandley 1 hour ago
            It depends, and that’s the point.

            It’s such a wide concept. Essentially it boils down to how a brain processes sensory information and at what point it becomes overwhelmed.

            We all have tolerances set at different gauges. It’s a disability if it’s at odds with the environment a person finds themselves in.

          • iinnPP 1 hour ago
            The problem is assuming the social cues are important at this point in evolution.

            I'd say the opposite is true, frankly. I'm more worried about people's inability to follow simple instructions, like making a hamburger correctly.

            • hoppp 28 minutes ago
              Social cues are important for reproduction. An autist guy might not notice when girls are attracted to him. So the chances of reproduction are lower.
        • krapp 1 hour ago
          This isn't /g/ what are you talking about?