Duke University Medical Center-led research has identified a human-specific DNA enhancer that regulates neural progenitor proliferation and cortical size. Small genetic changes in HARE5 amplify a key developmental pathway, resulting in increased cortical size and neuron number in experimental models. Findings have implications for understanding the genetic mechanisms underlying neurodevelopmental disorders.

Humans possess a significantly larger and more complex cerebral cortex compared to other species, contributing to advanced cognitive functions. Comparative genomics research has identified Human Accelerated Regions (HARs), segments of non-coding DNA with human-specific genetic changes. Many HARs are located near genes associated with brain development and neural differentiation.

Because thousands of HARs have been identified and linked to brain-related genes, the next critical step is to investigate how these regulatory elements actively shape human brain features.