Major Autism Study Uncovers Biologically Distinct Subtypes

Researchers at Princeton University and the Simons Foundation have identified four clinically and biologically distinct subtypes of autism, marking a transformative step in understanding the condition's genetic underpinnings and potential for personalized care. Analyzing data from over 5,000 children in SPARK, an autism cohort study funded by the Simons Foundation, the researchers used a computational model to group individuals based on their combinations of traits. The study, published in Nature Genetics, found that each subtype exhibits distinct developmental, medical, behavioral, and psychiatric traits, and importantly, different patterns of genetic variation.

Key Takeaways:

• Four distinct subtypes of autism have been identified: Social and Behavioral Challenges, Mixed ASD with Developmental Delay, Moderate Challenges, and Broadly Affected.
• Each subtype has distinct developmental, medical, behavioral, and psychiatric traits, and different patterns of genetic variation.
• The study used a 'person-centered' approach that considered a broad range of over 230 traits in each individual, from social interactions to repetitive behaviors to developmental milestones.
• Individuals in the Social and Behavioral Challenges group show core autism traits, including social challenges and repetitive behaviors, but generally reach developmental milestones at a pace similar to children without autism.
• The study found that each subtype has a unique genetic profile, with distinct genetic mutations and affected biological pathways.
• The researchers identified divergent biological processes affected in each subtype, suggesting that there is not just one biological story of autism, but multiple distinct narratives.
• The study found that autism subtypes differ in the timing of genetic disruptions' effects on brain development, with some mutations becoming active later in childhood.
• The team used a close integration of interdisciplinary expertise in genomics, clinical psychology, molecular biology, computer science, and modeling to analyze the data.
• The study's findings could reshape both autism research and clinical care, helping clinicians anticipate different trajectories in diagnosis, development, and treatment.

Statistics:

• The study included data from over 5,000 children in SPARK, an autism cohort study funded by the Simons Foundation.
• The four subtypes account for approximately 95% of the participants in the study, with the Social and Behavioral Challenges group making up around 37%, the Mixed ASD with Developmental Delay group making up around 19%, the Moderate Challenges group making up around 34%, and the Broadly Affected group making up around 10%.
• The study found that 40% of the participants in the Broadly Affected group had a high level of developmental delays, compared to 10% in the Social and Behavioral Challenges group.
• 37% of the participants in the Social and Behavioral Challenges group experienced co-occurring psychiatric conditions, compared to 12% in the Mixed ASD with Developmental Delay group.
• The study found that the Mixed ASD with Developmental Delay group had a higher proportion of rare inherited genetic variants, while the Broadly Affected group had a higher proportion of damaging de novo mutations.

Sources:

• ENPublishing (2025) - "Princeton University: Major autism study uncovers biologically distinct subtypes, paving the way for precision diagnosis and care" - http://www.enpublishing.co.uk
• Nature Genetics (2025) - "Decomposition of phenotypic heterogeneity in autism reveals underlying genetic programs" - July 9, 2025.
• Simons Foundation (2025) - "SPARK Autism Cohort Study" - funded by the Simons Foundation.
• National Institutes of Health (2025) - "U.S. National Institutes of Health" - supported research.
• Lewis-Sigler Institute for Integrative Genomics (2025) - "Princeton Precision Health" - supported research.
• Princeton University (2025) - "Princeton Precision Health initiative" - supported research.