Of Mice and Men??

Now Weissman says he is thinking about making chimeric mice whose brains are 100 percent human. He proposes keeping tabs on the mice as they develop. If the brains look as if they are taking on a distinctly human architecture — a development that could hint at a glimmer of humanness — they could be killed, he said. If they look as if they are organizing themselves in a mouse brain architecture, they could be used for research.

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