In the second half of the study, the UCLA team looked at the two genes' presence in the developing human brain. While CDH9's presence appeared minimal, the scientists discovered that CDH10 was most active in the fetal brain's frontal cortex, a region critical to language, social behavior and complex thought processes such as judgment.
"This is a landmark finding," Geschwind said. "It's no coincidence that a gene linked to autism has a higher concentration in key brain regions that regulate speech and the ability to interpret social interaction. Our research suggests that CDH10 is switched on at a very early stage and plays an important role in regulating the developing brain. This prenatal activity somehow makes the infant more susceptible to autism."
By influencing the development of important brain structures, CDH10 provides a tangible link between genes, brain circuitry and a child's future behavior, Geschwind noted. The discovery also opens up a number of intriguing next steps for research, including the possibility of an imaging study to explore whether the gene behaves differently in the autistic brain.
The DNA samples and clinical data were provided by families who donated blood to the Los Angelesbased Autism Genetic Resource Exchange (AGRE), a program created and funded by Cure Autism Now, which merged with Autism Speaks in 2007.
"When parents like me first formed AGRE, this was our dream, that talented scientists would use our gene bank to collaborate and bring us closer to understanding autism," said Jon Shestack, co-founder of Cure Autism Now and a board member of Autism Speaks. "AGRE has played an important role in almost every major autism genetics paper in the past five years."
Autism is a complex brain disorder that strikes in early childhood. The condit
|Contact: Roxanne Moster|
University of California - Los Angeles