Key Autism Genes Appear Consistent Across Ancestries, Major Study Finds

For decades, scientists trying to crack the genetics of autism have drawn almost exclusively from people of European descent. That narrow focus has left millions of families wondering whether those discoveries apply to them at all. Now, a new analysis of more than 15,000 Latin American individuals provides strong evidence that the answer is yes.

Researchers at the Icahn School of Medicine at Mount Sinai led the effort, sequencing DNA from thousands of Latin American participants and finding substantial overlap with the autism-linked genes identified in European-focused studies. As the authors concluded, “the biology of autism is consistent across populations and not impacted to any detectable degree by ancestry.”

That matters enormously for a group long overlooked by genetic science. Latin Americans are the largest minority in the United States and the world’s largest recently admixed population, a term reflecting centuries of mixed indigenous, European, and African heritage across the Americas. Yet this population has been dramatically underrepresented in autism genetics research, a gap that has contributed to less reliable genetic test results for Latin American patients.

This study, from the Genomics of Autism in Latin American Ancestries (GALA) Consortium and published in Nature Medicine, is the largest genetic sequencing study of autism in this population to date.

A Major New Study of Autism Genes Across the Americas

GALA draws from sites across North, Central, and South America, with data from eight locations contributing to the current findings. In total, 15,427 individuals were sequenced, including 4,717 with an autism diagnosis. Many enrolled as full family units, which allowed researchers to spot mutations that arose fresh in a child rather than being passed down from a parent. These “de novo” mutations tend to be extremely rare and, in genes tied to development, often highly damaging.

A statistical tool called TADA helped the team scan the genome for genes where those damaging mutations clustered in people with autism compared to unaffected siblings and controls. From that scan, 35 genes reached genome-wide significance, a threshold strong enough to make chance an unlikely explanation. Sixteen cleared an even higher bar.

Among those 35 are some of the most studied names in autism research: PTEN, SHANK3, CHD8, SCN2A, SYNGAP1. Each was identified primarily through research on European populations. Seeing them surface at comparable rates in Latin American participants is compelling evidence that autism’s core genetic architecture holds regardless of ancestry.

What ‘Highly Constrained’ Autism Genes Actually Mean

Central to the study is a concept called genomic constraint. Some genes are so essential to development that natural selection has spent generations purging harmful mutations from the population. Variants in these genes are extraordinarily rare, which is why finding them concentrated in people with autism is such a meaningful signal. It suggests the gene is not just coincidentally disrupted but genuinely driving the condition, making these variants particularly valuable for diagnosis and, eventually, treatment.

Going into this work, a real concern was whether testing tools built almost entirely from European genetic data would hold up for Latin American patients. For the most critical genes, the answer was yes. Patterns were consistent across ancestry groups, lending support to existing genetic testing approaches provided population-specific data are incorporated.

Where a gap did emerge was in broader clinical testing. Standard diagnostic software flagged disease-causing variants for roughly 4.3% of Latin American participants, compared to approximately 5.5% of non-Latin American participants. Researchers suggest the difference likely reflects clinical databases still heavily weighted toward European genetic data, which makes it harder to interpret what a specific variant means for patients from other backgrounds.

Closing the Gap in Autism Genetic Testing

That gap has consequences families feel directly. When a child with autism undergoes genetic testing and comes back with an inconclusive result, it does not mean nothing is genetically wrong. It may simply mean the databases clinicians rely on were not built from enough people who look like that child, a shortfall documented across diverse patient populations for years. Past research has found high rates of inconclusive results among non-European patients, and the GALA findings help explain the mechanism behind it.

Researchers point to possible paths forward. To start. focus on detecting newly arising mutations, which are often more informative for gene discovery than inherited ones, and build reference databases that reflect genetic diversity from all populations, not just European ones. Both changes could help more Latin American families get actionable answers from genetic testing, a need that has gone largely unaddressed in clinical practice.

Also gaining support through this study are several emerging autism gene candidates, including MARK2, YWHAG, PACS1, RERE, SPEN, GSE1, GLS, TNPO3, and ANKRD17, each of which appeared consistently in both Latin American and non-Latin American cohorts.

Autism genetics spent years building its foundation on a narrow slice of humanity. What this study suggests is that the core genetic drivers of autism were never uniquely European. They were always shared across humanity.

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Disclaimer: This article is based on peer-reviewed scientific research published in an academic journal. It is intended for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making any health-related decisions.

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