Susan Swanberg's research into the genetic roots of autism illustrates well the complexity of the disorder — and why it is necessary in autism science to understand genetics. Swanberg explains that what emerges in a child with autism — characterized by poor verbal and communication skills, repetitive behaviors and an inability to form social connections — is likely the end result of a variety of different events, depending on the child.

“There may be up to 20 genes involved in autism spectrum disorders, with many different combinations of an unknown number of these 20 genes involved in each person,” she said.

Susan Swanberg (right) and Janine LaSalle discuss progress on research related to hindbrain development in autism.

Swanberg, a participant in the UC Davis MIND Institute's Autism Research Training Program, previously did research on cellular aging in animals. Her research now focuses on where she thinks some of the answers to autism are — the cerebellum, pons and medulla oblongata, which are parts of the hindbrain. “There is evidence that the serotonergic neuronal network may be dysfunctional in at least a subset of autism cases,” Swanberg said. She hypothesizes that, since this network develops from neurons in the hindbrain, it is possible that something may go awry very early in development that causes defects in serotonin production or regulation.

As part of the ARTP, Swanberg developed a project in which she will explore expression of the MeCP2 gene in the brains of children with autism. This gene is involved in defects in cortical function and in Rett syndrome, an autism spectrum disorder with a known genetic cause. Swanberg is considering the role of MeCP2 in other forms of autism and other parts of the brain. “I want to know if it is more broadly implicated in autism and specifically in hindbrain dysgenesis,” she said.

For Swanberg, the ARTP has initiated a career shift. “The program has helped accomplish my goal of becoming a human geneticist,” she said.

“Susan is a great example of how a Ph.D. trained in another scientific field can make the transition to autism research through this program,” said Janine LaSalle, an associate professor of medical microbiology and immunology and Swanberg's primary ARTP mentor. “She is already getting very promising results.”