GTF2I Gene Links Williams Syndrome Sociability and Autism

Author: University of California - San Diego
Published: 28 Feb 2024 - Updated: 4 Nov 2026
Publication Details: Peer-Reviewed | Research / Study Analysis

Table of Contents:
Synopsis - Definition - Overview - FAQs - Insights, Updates - Related Content

Synopsis

This research from the Sanford Stem Cell Institute at UC San Diego, published in the peer reviewed journal Cell Reports on February 27, 2024, examined why people with Williams syndrome are unusually sociable while people with the opposite genetic change, 7q11.23 duplication syndrome, often have autistic traits. Using brain organoids grown from stem cells without the GTF2I gene, the team found smaller organoids with more cell death, lower electrical activity and faulty synapses. The results suggest GTF2I is the main gene behind these social differences and could guide future treatments, which interests families affected by Williams syndrome, autism and related conditions.*

At a Glance

• 1 - Mice and fruit flies that lack GTF2I are more sociable than usual.
• 2 - 7q11.23 duplication syndrome is linked to autism, social phobia and selective mutism.
• 3 - Williams syndrome is caused by the deletion of about 25 genes on chromosome region 7q11.23.
• 4 - People with Williams syndrome are friendly with strangers, which can leave them open to abuse and bullying.

Topic Definition

Williams Syndrome

Williams syndrome is a rare genetic condition caused by the deletion of about 25 genes on chromosome 7 in the 7q11.23 region. It is marked by an unusually friendly and talkative personality, mild to moderate intellectual disability, distinctive facial features, heart and blood vessel problems, and strengths in language and music, and people with it may need support to stay safe from exploitation.

Overview

Individuals with the neurodevelopmental disorder Williams syndrome have a gregarious "cocktail party" personality, while those with the opposite genetic alteration, in contrast, tend to have autistic traits and are prone to struggle socially. Now, thanks to new findings by researchers at the Sanford Stem Cell Institute at University of California San Diego, scientists have a better understanding of why. The research, published February 27, 2024 in Cell Reports, may help explain variations in human personality and could even lead to the development of a treatment that makes it easier for some individuals with autism to better function in society.

Often referred to as "the opposite of autism," Williams syndrome is a rare genetic condition caused by the deletion of about 25 genes in the 7q11.23 chromosomal region. This alteration produces a constellation of symptoms like heart disease and developmental delay. It characteristically features a strikingly engaging personality with high sociability, talkativeness, and a vocabulary that masks a typically below-average IQ.

The social strengths of Williams syndrome, however, are a double-edged sword. Individuals with this seemingly paradoxical condition know no strangers, making them particularly vulnerable to abuse and bullying.

Instead of a deletion of genes in the 7q11.23 chromosomal region, some people's DNA features a duplication, resulting in behaviors that are, in turn, quite the opposite of those exhibited by individuals with Williams syndrome. Those with this opposing rare genetic alteration - known as 7q11.23 duplication syndrome - customarily experience symptoms including autism, social phobia, and selective mutism.

While the broader genetic region underlying Williams syndrome has previously been studied, scientists at UC San Diego hypothesized that one gene in particular - GTF2I - is predominantly responsible for the social variation seen in the disorder.

"I like to describe this gene as the gene of prejudice," said Alysson Muotri, PhD, director of the UC San Diego Integrated Space Stem Cell Orbital Research Center and lead author on the paper. "Without it, everyone in the world is your friend."

To learn more about its role, researchers used human pluripotent stem cells to create mini organs that mimic the human brain during fetal development - minus GTF2I. At 2 months of age, these so-called brain organoids were smaller than ones with GTF2I. Indeed, loss of the gene, they found, resulted in increased cell death, decreased electrical activity, and defects in synapses, the electrochemical connections that allow neurons to communicate with each other.

Researchers still don't fully understand why the alteration of the GTF2I gene affects the brain like it does. The team hypothesizes that increased cell death reduces the number of cells in the brain - and, thus, its electrical activity. It's also possible that the gene helps repair synapses, meaning that those without it have a greater number of such that go unrepaired.

Hope For a Better Treatment

Hundreds of genes have been tied to autism, but GTF2I "is the only gene we are aware of that regulates socialization more directly," Muotri said. The new research suggests that, when it comes to sociality, the gene is the main player in fetal brain development. Indeed, individuals without either Williams or 7q11.23 duplication syndromes - that is to say, most of us - have a balanced gene dosage of GTF2I, and are neither hyper- nor hypo-social.

The findings from the new study align with previous work that has demonstrated hypersociability in animals who lack GTF2I. For example, fruit flies who don't have the gene prefer to eat together, without the usually obligatory "social bubble," and mice who've had the gene deleted are friendlier than most. Moreover, incredibly, alterations to a gene that controls the function of GTF2I - potentially turning it off - may be at least partially responsible for the loving, friendly disposition of domesticated dogs compared to wild wolves.

Thanks to the findings of Muotri's team, hope may be on the horizon for those with GTF2I-linked autism. The research has paved the way for the potential development of a drug that regulates its expression, facilitating social interaction for affected individuals. Such treatment may also help those who have a normal GTF2I gene that was "turned off" by the epigenome, biochemical regulators that modify how our genes are expressed during development and across the lifespan.

The team's work also sheds light on the evolution of human sociality, Muotri contends. Chimpanzees - the closest evolutionary relative of humans - are social but only to an extent, preferring to deal with just a few other chimps at once. Humans, on the other hand, "create large communities in which we trust each other without really knowing each other," he said. Case in point: "When you enter a plane, you don't ask to see the pilot's license."

"GTF2I is most likely among the genes that help humans achieve that safe balance, where we trust the community but sometimes don't trust each other to the same degree," he added. "There's a fine-tuning of socialization in humans you don't see in other species."

What results is the ability to effectively collaborate - and such collaboration, Muotri asserts, has been key to humanity's greatest achievements:

"It's when we cooperate that we can put a man on the moon. It's when we cooperate that we can decode the human genome. Because we work together."

Co-authors

Co-authors of the study include Jason W. Adams, Annabelle Vinokur, Janaína S. de Souza, Charles Austria, Bruno S. Guerra, Roberto H. Herai, and Karl J. Wahlin, all at UC San Diego.

Funding

The study was funded, in part, by the National Institutes of Health (grants R01MH100175, R01NS105969, P01 NICHD033113, MH123828, R01NS123642, R01MH127077, R01ES033636, R21MH128827, R01AG078959, R01DA056908, R01HD107788, R01HG012351, R21HD109616, R01MH107367 and 5T32GM007198, 1-DP2-OD006495-01), the United States Department of Defense (W81XWH2110306) and a CARTA Fellowship.

COI Statement

Alysson Muotri is a cofounder and has equity interest in TISMOO, a company dedicated to genetic analysis and brain organoid modeling focusing on therapeutic applications customized for ASD and other neurological disorders with genetic origins.

Frequently Asked Questions

NOTE: Researched FAQs by Disabled World (DW)

How common is Williams syndrome?

It is rare, affecting roughly 1 in 7,500 to 1 in 10,000 people, according to commonly cited estimates.

Is Williams syndrome inherited?

Most cases occur by chance, but a person with Williams syndrome has a 50 percent chance of passing it to each child.

What are brain organoids?

They are tiny, simplified clusters of brain tissue grown from stem cells in the lab, used to study how the human brain develops.

What is 7q11.23 duplication syndrome?

It is a rare condition in which the same region missing in Williams syndrome is duplicated, often causing speech delay, anxiety and autistic traits.

How is Williams syndrome diagnosed?

It is usually confirmed with a genetic test such as chromosomal microarray or FISH that detects the missing genes.

Can a drug change social behavior in autism?

No such drug is available. This research suggests GTF2I could be a future target, but treatments would need years of testing.

What support helps people with Williams syndrome?

Support may include heart monitoring, speech and occupational therapy, special education, safety training and help with anxiety.

Why are people with Williams syndrome vulnerable to abuse?

Their strong trust and friendliness toward strangers can make it harder for them to recognize people who mean them harm.

Insights, Analysis, and Developments

Editorial Note: Williams syndrome and 7q11.23 duplication syndrome act like a natural experiment, showing how changing the dose of a small set of genes can push social behavior in opposite directions. Pinning much of that effect on one gene gives researchers a clearer target, though the work was done in lab-grown brain tissue and any treatment is far off. It is also a reminder that very high sociability brings its own risks, and people with Williams syndrome often need support to stay safe. Families affected by either condition can benefit from genetic counseling and from support groups focused on these rare syndromes.*

Attribution/Source(s): This peer-reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally issued as a press release by University of California - San Diego and published on 28 Feb 2024. Last updated on 4 Nov 2026. This content may have been edited for style, clarity, or brevity.

* Editorial additions by Ian C. Langtree.