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Hacker News front pageKrista Conger5 min readrelease notesintermediate

Human brain is two separate organs, Stanford Medicine-led research finds

Read on stanford.eduHN 654·257 comments

Summary

Stanford researchers discovered that the human brain develops from two separate progenitor lineages—one for forebrain/midbrain (Otx2) and one for hindbrain (Gbx2)—and used this insight to grow functional hindbrain neurons from pluripotent stem cells. This breakthrough provides a platform for studying brain‑stem diseases such as SMA and ALS and reshapes our understanding of brain evolution.

  • Forebrain/midbrain progenitors express Otx2, hindbrain progenitors express Gbx2; their chromatin states are mutually exclusive from gastrulation.
  • Human pluripotent stem cells were coaxed into functional hindbrain motor neurons that fire action potentials and express segment‑specific proteins.
  • The new hindbrain neuron model enables disease studies for SMA and ALS, which previously lacked accessible brain‑stem tissue.
  • A similar two‑origin brain pattern is found in chickens, zebrafish, and acorn worms, indicating an ancient evolutionary split.

Stem‑cell biologists and neuro‑disease modelers should care because the work enables reliable in‑vitro hindbrain neuron production for studying ALS, SMA, and related therapies.

5/10
neurosciencedevelopmental biologystem cellsdisease modelinggenetics

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