A Chromatin Accessibility Atlas of the Developing Human Telencephalon.

To discover regulatory elements driving the specificity of gene expression in different cell types and regions of the developing human brain, we generated an atlas of open chromatin from nine dissected regions of the mid-gestation human telencephalon, as well as microdissected upper and deep layers of the prefrontal cortex. We identified a subset of open chromatin regions (OCRs), termed predicted regulatory elements (pREs), that are likely to function as developmental brain enhancers. pREs showed temporal, regional, and laminar differences in chromatin accessibility and were correlated with gene expression differences across regions and gestational ages. We identified two functional de novo variants in a pRE for autism risk gene SLC6A1 , and using CRISPRa, demonstrated that this pRE regulates SCL6A1. Additionally, mouse transgenic experiments validated enhancer activity for pREs proximal to FEZF2 and BCL11A. Thus, this atlas serves as a resource for decoding neurodevelopmental gene regulation in health and disease. • ∼19,000 enhancers defined in nine regions of the developing human telencephalon • Chromatin dynamics correlate with sequence motifs and spatiotemporal gene expression • Identified cortical layer-specific enhancers and validated a layer 5 FEZF2 enhancer • Genetic variants from patients alter activity of an enhancer for an autism risk gene A high-resolution atlas of regulatory elements driving regional, temporal, and laminar gene expression programs in the developing human telencephalon reveals enhancers and genetic variants regulating human disease genes. [ABSTRACT FROM AUTHOR]