MICE WITH HUMAN BRAIN CELLS OFFER A TOOL TO STUDY DISEASE. ETHICISTS ASK: WHAT'S NEXT?

Summary from the TLDR newsletter

Researchers have developed a technique for installing millions of human brain cells into mice. The scientists bred mice that were missing most of their cerebral cortexes and then replaced a large part of those missing mouse cells with lab-grown human brain cells. This resulted in mice with human neurons that could be altered to approximate human brain conditions. The technique could potentially create better scientific models for studying neurodegenerative disease.