Autism Has No Single Cause. Here’s How We Know
Posted4 months agoActive4 months ago
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Autism ResearchGenetics and EnvironmentNeuroscience
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Autism Research
Genetics and Environment
Neuroscience
The article discusses how research shows that autism has no single cause, and the discussion revolves around exploring various potential factors contributing to autism, such as gut health, genetics, and environmental exposures.
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Sep 11, 2025 at 4:22 PM EDT
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ID: 45215745Type: storyLast synced: 11/20/2025, 3:41:08 PM
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Gut health isn’t mentioned in the article, so it seems like a good point to bring up.
"However, the association did not persist when using sibling controls, implying that this association is due to familial confounding by genetic and/or environmental factors." - https://jamanetwork.com/journals/jamapsychiatry/fullarticle/...
> Other factors that have been linked to autism include people being born prematurely or through cesarean section, as well as pregnant people having obesity, using certain medications (such as the antiseizure drug valproate) and the pain reliever acetaminophen (the active ingredient in Tylenol) and being exposed to air pollution. The strength of the evidence for these links varies, though, and the increases in risk tend to be small. The evidence is also only correlational, meaning it can’t establish what caused what.
> Acetaminophen is also usually used as a fever reducer, which pregnant people might take if they are fighting an infection. Both infections and uncontrolled fevers during pregnancy have been linked to higher rates of autism. “We know that the neurodevelopmental outcomes of having an uncontrolled fever are worse than what we’re observing for acetaminophen,” Mandell says.
Not only that, but the effects measured in the present studies have never even considered varying titers in vaginal canals during births, at least as far as I know.
Science isn’t gospel, don’t treat it like so. The original comment is a hypothesis, but it's based on existing evidence.
Here's some information from another comment,
https://news.ycombinator.com/item?id=45215745
Which painkillers? Do you have a citation for that? Note that ibuprofen is generally prohibited in pregnancy.
Here’s some additional information from another paper
> The gut microbiome has been implicated in the pathophysiological mechanisms of ADHD through the MGBA. Alterations in the MGBA contribute to neuroinflammation and oxidative stress, leading to ADHD core symptoms and associated comorbidities such as sleep disturbances. There is some evidence indicating maternal stress and the use of acetaminophen, which is a common pain reliever and fever reducer, may increase the risk of ADHD in offspring during pregnancy
https://www.mdpi.com/2075-1729/14/10/1234
No, that is false. The state Democratic parties are going to cut far, far more.
> the Trump administration
You just knew that was coming. My previous statement is unmentioned of course, despite the obviousness of it. That's how propaganda works. Roughly 6-7% of this article.
> The OBBBA language that cut and restructured Medicaid included explicit exemptions for people classified as "medically frail", which in federal Medicaid law covers people with physical, intellectual, and developmental disabilities.
Just kidding, we know full well that's not in this article.
> biology ... genes
For a article on a medical topic, this article says almost nothing about the underlying biology of autism, at least nothing more than an American Eagle ad. It is really all about that closing, to keep the fire going.
Propaganda. Sorry I couldn't get to this article sooner, I was editing Wikipedia on healthcare topics, pretty much fighting against everything this article is about.
Autisms are biologically caused by disruptions in early brain development that alter how synapses are formed, pruned, and regulated, producing imbalances in excitatory and inhibitory signaling across neural circuits. Most cases trace to combinations of genetic variants—some rare, high-impact mutations affecting synaptic scaffolding (e.g., postsynaptic density proteins), neuronal excitability (ion channels), chromatin remodeling, or transcriptional control, and many common variants with smaller effects—while prenatal factors such as maternal immune activation, teratogens, or perinatal stress can act as modifiers. These converging influences disturb synaptic wiring, circuit dynamics, developmental timing, and gene-expression programs, leading to atypical brain connectivity: often locally hyperconnected yet underintegrated across distant regions. This altered network balance underlies the sensory, communicative, and behavioral traits recognized as the autism spectrum.
Synapse Formation and Balance:
– Faulty assembly and regulation of excitatory and inhibitory synapses.
– Leads to unstable network tuning, “noisy” signaling, and altered local vs. global connectivity.
Neuronal Firing and Circuit Dynamics:
– Changes in ion channel function distort how neurons spike and synchronize.
– Affects rhythmic activity (oscillations) important for sensory integration and social cognition.
Neurodevelopmental Timing:
– Mistimed growth, migration, and pruning of neurons.
– Results in atypical wiring patterns: often hyperconnected locally but underconnected long-range.
Gene Expression Control:
– Master regulators fail to coordinate large developmental programs.
– Produces ripple effects across hundreds of downstream pathways, compounding small errors.
https://news.ki.se/new-study-links-dopamine-to-autism-sympto...
From the study:
„ This suggests that increased Ca2+ levels can compensate for deficits in β2-nAChR function and restores DA release.“
Calcium plays an important role here: https://www.stridesaba.com/calciums-role-in-supporting-indiv...
"The effects of parental occupational exposures on autism spectrum disorder severity and skills in cognitive and adaptive domains in children with autism spectrum disorder" https://www.sciencedirect.com/science/article/pii/S143846392...
The person leading this study, Erin C. McCanlies, was forced out of the CDC, her division eliminated and she went into early retirement from the CDC. https://www.psypost.org/scientist-who-linked-autism-to-chemi...
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"The findings suggest that workplace exposures to several specific chemical classes were associated with worse outcomes in children with ASD. One of the strongest and most consistent patterns involved plastics and polymer chemicals. Fathers’ exposure to plastics was associated with lower scores across all cognitive and adaptive skill domains, including language, motor coordination, daily living skills, and overall functioning. When both parents were exposed, the deficits appeared to compound.
“I was surprised how strongly and consistently plastics and polymers stood out as being linked with multiple developmental and behavioral outcomes including irritability, hyperactivity, and daily living,” McCanlies told PsyPost.
Exposure to ethylene oxide—commonly used in hospital sterilization—was also linked to more severe autism symptoms, lower expressive language abilities, and poorer adaptive functioning. Similarly, parental exposure to phenol (used in construction, automotive, and some consumer products) and pharmaceuticals was associated with increased ASD severity and more pronounced behavioral challenges, especially hyperactivity and stereotyped behavior.
While the results do not imply that all children exposed to these chemicals will develop more severe symptoms, the patterns suggest that early life exposure to workplace toxicants may amplify certain developmental difficulties in children who already meet criteria for ASD. The study provides one of the most detailed looks to date at how parental occupation may relate not just to diagnosis, but to variation in how autism is expressed.
“Our findings suggest that certain parental workplace exposures may be related not just to autism, but to worse symptoms and autism behaviors,” McCanlies explained."