Mapping origins of variation in neural trajectories of human pluripotent stem cells [RNA-seq BRNiPSC246]

Variability between human pluripotent stem cell (hPSC) lines remains a challenge and opportunity in biomedicine. We identify differences in the spontaneous self-organization of individual hPSC lines during self-renewal that lie along a fundamental axis of in vivo development. Distinct stable and dynamic transcriptional elements were revealed by decomposition of RNA-seq data in pluripotency and early lineage emergence. Stable differences within pluripotency predicted regional bias in the dynamics of neural differentiation that were also observed in large collections of hPSC lines. Using replicate human induced PSC (hiPSC) lines and paired adult tissue, we demonstrate that cells from individual humans expressed unique transcriptional signatures that were maintained throughout life. In addition, replicate hiPSC lines from one donor showed divergent expression phenotypes driven by distinct chromatin states. These stable transcriptional states are under both genetic and epigenetic control and predict bias in subsequent forebrain and hindbrain neural trajectories. These results define mechanisms controlling transcription in pluripotency to first establish human neural diversity.