Teams of physicians and scientists at UC Davis' MIND Institute have launched the nation's most comprehensive assessment of children with autism to detect the biological and behavioral patterns that define subtypes of the disorder.

Called the Autism Phenome Project, the large-scale study will enroll 1,800 children — 900 with autism, 450 with developmental delay and 450 who are typically developing — who will undergo thorough medical evaluations in addition to systematic analyses of their immune systems, brain structures and functions, genetics, environmental exposures and blood proteins. Children will be 2 to 4 years old when they begin participating in the study, and their development will continue to be evaluated over the course of several years. The first phase of the research is funded by the MIND Institute and philanthropic donations.

"Children with autism clearly are not all the same," said David Amaral, research director of the MIND Institute and co-director of the project. "The tremendous variation leads us to believe that autism is a group of disorders rather than a single disorder — several autisms versus one autism. We are determined to provide the specific biomedical and behavioral criteria that accurately define distinct subtypes."

Autism has common hallmarks: difficulties initiating and sustaining social interactions, impaired communication skills and restricted, repetitive patterns of behavior. However, these hallmarks vary in severity.

In addition, some children with autism can have co-existing conditions such as cognitive impairments, seizures, coordination and gastrointestinal difficulties, while others do not. This heterogeneity has been a major obstacle to progress in autism science.

Another obstacle involves access to reliable data. Autism science includes many quality studies on specific aspects of the disorder — from genetics and immunology to behavior and imaging — that can be difficult to combine and compare. With the Autism Phenome Project, MIND Institute researchers aim to overcome this limitation.

"We spent two years designing the project so that it would be both comprehensive in scope and fully capable of integrating data across disciplines," said Amaral, a neuroscientist who specializes in brain systems involved in memory, emotion and social behavior.

He added, "Our goal is to identify specific types of autism and develop a database of biomedical information that can be shared with the worldwide community of autism scientists. This is crucial to refining our understanding of autism and to developing targeted treatments for a specific 'type' of autism as early as possible so children can reach their fullest potential."

According to Thomas Insel, a physician who is director of the National Institute of Mental Health, the Autism Phenome Project is an important new direction in autism research. "Multifaceted biomedical approaches are exactly what is needed right now," said Insel.

While the Autism Phenome Project is ambitious, Amaral said he believes its successful completion will shorten by decades the road to discovering the causes and treatments of autism, a neurodevelopmental disorder that now affects one in 166 children in the United States.

For more information, visit www.mindinstitute.org.