Scientists from Mayo Clinic and Yale University have uncovered potential origins of autism spectrum disorder (ASD).
By studying human “mini-brain” models or organoids, the team observed an imbalance in specific brain cells, namely, excitatory cortical neurons.
This imbalance was seen in the forebrain region of individuals with autism and was notably associated with their head size.
Organoids are tiny, three-dimensional models of the brain.
Alexej Abyzov, Ph.D., from the Mayo Clinic, emphasized how this technology can mirror the brain’s development during the time in the womb, a crucial period believed to be when ASD originates.
ASD is a neurological condition affecting social interactions and behavior. Its spectrum nature means it includes a range of conditions, from autism to Asperger’s syndrome.
Roughly 1 out of 36 children in the U.S. is diagnosed with ASD, as reported by the Centers for Disease Control.
The research process began by transforming skin cells from individuals with ASD into miniature brain-like structures.
These cells were reprogrammed into a stem-cell-like state, making them versatile and capable of developing into any cell type, including brain cells.
To gain deeper insights, researchers applied a technique known as single-cell RNA sequencing to examine gene patterns in individual brain cells.
By studying over 664,000 brain cells across three developmental stages, they identified changes in certain genes responsible for cell development during early brain formation.
This investigation is a continuation of over a decade of research by Dr. Abyzov and his colleagues, such as Dr. Flora Vaccarino from Yale University.
In a previous groundbreaking study, they highlighted molecular differences in organoids from people with and without autism. A particular gene called FOXG1 was identified as a potential trigger for ASD.
Dr. Abyzov envisions a future where autism risks can be determined, and possibly even prevented, before a child is born using prenatal genetic testing.
However, achieving this would need a comprehensive understanding of how brain regulation gets altered during development. “Organoids could play a pivotal role in bridging this knowledge gap,” says Dr. Abyzov.
The study was published in Nature Neuroscience.