Ethics of humanized mice
The recent stories “Human cells rev up mouse brains” (SN: 4/6/13, p. 16) and “Of mice and man” (SN: 3/23/13, p. 22) drove home to me that human-animal hybrids are now reality. In science fiction stories with such hybrids, a big part of the plot is the resultant ethical gray area: There are certain standards for animal research, and much stricter standards for human research. What standards apply to animals that have a significant payload of human cells? Brain research has the most obvious ethical implications, but what makes a “human” is complex and probably involves other parts such as the immune system. (I would be interested if mice with humanized immune systems showed changes in learning ability.)
Virginia Brock, Rock Island, Ill.
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