Ethical objections to human brain cell transplants in mice

A post linking to a Nature paper criticizes experiments it says researchers call “xenocortication.” According to the author, transplanted human brain cells colonized 90% of the cortex in genetically altered mice and partially restored lost function. The author also says some mice were exposed to low oxygen to cause brain damage. They argue the work crossed an ethical line and say Stanford’s animal-care and stem-cell research oversight committees approved it.