AI uncovers genetic blueprint of the brain's largest communication bridge (keck.usc.edu)

Researchers at USC’s Stevens INI used a new AI-powered tool to map the genetic architecture of the corpus callosum—the brain’s largest interhemispheric bridge—and published their results in Nature Communications. The tool automatically locates and measures the corpus callosum across different MRI types, enabling analysis of brain scans and genetics from more than 50,000 people (ages from childhood to late adulthood) drawn from large cohorts including ABCD and UK Biobank. By running large-scale imaging-genetics analyses, the team identified dozens of genetic loci that influence the corpus callosum’s area and thickness, found that distinct gene sets govern those two features, and showed many implicated genes are active prenatally in cell growth, programmed cell death, and axon wiring across hemispheres. The work is significant because it provides a reproducible “genetic blueprint” linking specific molecular pathways to variation in a structure long tied to ADHD, bipolar disorder, Parkinson’s and other conditions. The study also reports genetic overlap between the corpus callosum and the cerebral cortex, suggesting shared developmental mechanisms that could underlie disease risk. By releasing the AI tool publicly, the team dramatically speeds up and scales precise structural measurements—reducing years of manual work to hours—and gives the neuroscience community a practical platform to accelerate discovery into brain development, diagnostics, and therapeutic targets.