This is what's happening. This is why.
For families caught in the long silence of unexplained neurological difference, a name can be a form of mercy. Mayo Clinic researchers, working with collaborators at the University of North Carolina at Chapel Hill, have identified variants in the SPTBN1 gene as the cause of a previously unnamed neurodevelopmental disorder — a discovery published in Nature Genetics and drawn from the study of 29 patients whose symptoms ranged from seizures to intellectual disability to language delay. The finding does not yet offer a cure, but it offers something nearly as profound: the end of not knowing, and a scientific foundation from which treatment may one day be built.
- Families of children with unexplained neurological symptoms have endured years of inconclusive testing — the discovery of SPTBN1 as a causal gene now gives clinicians a concrete place to look.
- Twenty-eight distinct genetic variants were found across 29 patients, most arising spontaneously rather than inherited, making the disorder difficult to recognize and easy to miss on standard panels.
- The clinical picture is strikingly variable — seizures in one child, motor delays in another, behavioral abnormalities in a third — because different variants damage the beta-two spectrin protein in different ways, obscuring the shared genetic root.
- Researchers used computational modeling, human and mouse cell cultures, and living animal studies to map how each variant disrupts the protein's role in building brain connectivity.
- SPTBN1 can now be added to genetic testing panels, transforming it from an invisible cause into a diagnosable condition — a shift that ends diagnostic odysseys and opens the door to targeted therapeutic research.
For families searching for answers about a child's atypical brain development, the journey can stretch across years of specialists and inconclusive tests. Mayo Clinic researchers have now identified a significant piece of that puzzle: variants in a gene called SPTBN1 are responsible for a neurodevelopmental disorder affecting how the brain forms and connects, with findings published in Nature Genetics.
The research was led by Margot Cousin, a translational genomics researcher at Mayo Clinic's Center for Individualized Medicine, who suspected SPTBN1 held answers for patients with unexplained neurological symptoms. Her team studied 29 individuals experiencing language and motor delays, intellectual disability, seizures, behavioral problems, and unusual facial features — identifying 28 distinct genetic variants, most of them spontaneous mutations rather than inherited ones.
What complicated the work was the disorder's variability. No two patients presented identically, making it difficult to recognize a shared genetic origin. Through computational modeling, cell cultures, and living mouse studies, the team found that SPTBN1 encodes a protein called beta-two spectrin, critical for building the communication networks between brain cells. Different variants damaged this protein in different ways — some destabilizing it, others disrupting its interactions — which explained why patients looked so clinically distinct despite sharing the same genetic root.
The discovery transforms uncertainty into diagnosis. SPTBN1 can now be included in genetic testing panels, giving clinicians a place to look when standard tests return empty and giving families, at last, an explanation. The cell and animal models developed during the study will serve as the foundation for exploring potential treatments — no cure exists yet, but the moment a scattered collection of cases becomes a recognized condition is, in rare disease research, the moment everything else becomes possible.
For families searching for answers about why their child's brain develops differently, the diagnostic journey can stretch across years—multiple specialists, countless tests, mounting uncertainty. Mayo Clinic researchers have now identified a piece of that puzzle. They've discovered that variants in a gene called SPTBN1 are responsible for a neurodevelopmental disorder that affects how the brain forms and connects. The finding, published in Nature Genetics, represents the first solid foothold toward understanding the condition and eventually treating it.
The research began with a hunch. Margot Cousin, a translational genomics researcher at Mayo Clinic's Center for Individualized Medicine, suspected SPTBN1 held answers for patients with unexplained neurological symptoms. Working with collaborators at the University of North Carolina at Chapel Hill, her team studied 29 people whose brains weren't developing typically. These patients experienced language delays, motor delays, intellectual disability, seizures, behavioral problems, and unusual facial features. The team identified 28 distinct genetic variants across these patients—most of them new mutations that arose spontaneously rather than inherited from a parent.
What made the work challenging was the sheer variability. No two patients looked exactly alike clinically, which made it hard to recognize they shared a common genetic root. But as Cousin and her colleagues dug deeper, using computational modeling, human cell cultures, mouse cell cultures, patient-derived cells, and living mouse studies, a pattern emerged. The SPTBN1 gene codes for a protein called beta-two spectrin, which is abundant in the brain and essential for building the networks that allow brain cells to communicate. Different variants damaged this protein in different ways—some made it unstable, others prevented it from interacting properly with neighboring proteins. These functional differences explained why patients presented so differently, even though they all carried SPTBN1 mutations.
The discovery matters because it transforms uncertainty into diagnosis. For years, families with affected children have faced what researchers call a diagnostic odyssey—the exhausting search for a name, a cause, an explanation. Now SPTBN1 can be added to genetic testing panels. When a child shows signs of neurodevelopmental delay and standard tests come back empty, clinicians can look here. They can tell families: this is what's happening. This is why.
But diagnosis is only the beginning. Cousin emphasizes that the real work lies ahead. The cell and animal models her team developed during this study will serve as laboratories for testing potential treatments. No cure exists yet. What exists now is understanding—the recognition that SPTBN1 variants cause this condition, the knowledge of how they damage the protein, and the tools to explore what might fix it. In rare disease research, that foundation is everything. It's the moment when a collection of isolated cases becomes a recognized condition, when families stop wondering if anyone else has what their child has, and when scientists can finally begin asking: what can we do about it?
Notable Quotes
The gene can now be included in genetic testing for people suspected of having a neurodevelopmental disorder, which may end the diagnostic odyssey these people and their families have endured.— Margot Cousin, PhD, Study Lead Author, Mayo Clinic
We can now provide patients with an answer to the root cause of disease, which is the most important first step toward finding a cure.— Margot Cousin, PhD
The Hearth Conversation Another angle on the story
Why did it take so long to connect these 29 patients if they all had the same gene problem?
Because they didn't look the same. One child might have seizures and intellectual disability; another might have mostly motor delays and behavioral issues. Clinically, they seemed like different conditions. It wasn't until the researchers had enough patients and could run sophisticated protein studies that the pattern became visible.
So most of these variants just appeared randomly in these kids—they didn't inherit them?
Right. Twenty-eight variants across 29 patients, and most were de novo, meaning they happened spontaneously during the formation of the egg or sperm. That's actually common in severe neurodevelopmental disorders, but it also makes them harder to track because parents don't carry the mutation.
What does beta-two spectrin actually do in the brain?
It builds the scaffolding that holds cells together and lets them communicate. Think of it as part of the infrastructure. If that protein is malformed or unstable, the whole network suffers. Brain development depends on precise connections forming at the right time.
If there's no treatment yet, what changes for these families right now?
Everything changes and nothing changes, in a way. They finally have an answer. They know it's not their fault, it's not random bad luck—it's a specific genetic cause. And they know researchers are now looking directly at this gene. That's the first step toward a cure.
How confident are researchers that they've actually found the culprit?
Confident enough that it's in Nature Genetics. They showed the variants damage the protein in multiple different systems—cells, mice, computational models. The gene itself has all the hallmarks of a rare disease gene. But the real test will be whether treatments that fix the protein actually help patients.