Genetic factors have been known to play a role in the development of autism, but the contribution of common genetic variations — those that crop up in at least 1 percent of the general population — to the disorder is not known. Randy Buckner and his colleagues at Harvard University developed a new, highly efficient approach to explore the effects of these variations on brain functions associated with autism.
Many of the hundreds of genes involved in brain development have common variations that presumably contribute to the typical diversity found in the general population. Buckner and his colleagues hypothesize that genetic predisposition to autism occurs when brain development is steered down an abnormal path through the combined influence of dozens — or even hundreds — of common variants, each with a small role. To determine the role of such variations in autism, Buckner and his team explored typical development and looked at parents of individuals with autism.
Data from a recently developed imaging tool called functional connectivity magnetic resonance imaging, or fcMRI, were collected for more than 3,000 typically developing individuals. These data allow researchers to examine basic properties of brain organization — such as which hemisphere is dominant for language, and whether typical connectivity patterns are present in brain systems used for thinking — and link differences in these properties to specific genetic variants.
Buckner and his colleagues have dubbed their effort the Brain Genomics Superstruct Project, as it builds on, or ‘superstructs,’ the collective foundation laid by previous work on autism, including the ongoing data samples collected through the Simons Simplex Collection. The team shared their rapid fcMRI protocol, which eases the burden of data acquisition by capturing imaging data in less than 15 minutes per participant. The researchers are also sharing the structural and functional MRI data collected through their project.