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Latest Advance in Chimeras

Researchers in the U.S. and China announced earlier this month that they made embryos that combined human and monkey cells for the first time. So far, these human-monkey chimeras (pronounced ky-meer-uhs) are no more than bundles of budding cells in a lab dish, but the implications are far-reaching, ethics experts say. 

In a glimpse of the potential effects, researchers at the University of Rochester in 2014 transplanted human fetal brain cells called astrocytes into young laboratory mice. They discovered that within a year the human cells had taken over the mouse brains. Moreover, standard tests for mouse memory and cognition showed that the altered mice were smarter.

Small Step Towards a Huge Ethical Problem

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The Conversation says this is a Small Step Towards a Huge Ethical Problem.

The embryos, which were derived from a macaque and then injected with human stem cells in the lab, were allowed to grow for 20 days before being destroyed.

We have a term for this type of life form: a chimera, named after the fire-breathing monster of Greek mythology that was part lion, part goat and part snake.

This research clearly has the “yuk factor”, meaning it’s likely to provoke moral revulsion. If pigs or monkeys are eventually developed with humanised features, it could cause major public opprobrium, perhaps setting back public acceptance of science significantly

Moral status is the concept of treating life forms according to their interests and capacities. It is already one of the most contested areas of practical ethics. Recent work on “speciesism” makes a compelling case that we have wrongly assigned animals a lower moral status. Despite this, human-nonhuman chimeras will probably be regarded as “lesser” than humans, though by how much it is difficult to determine.

Question of the Day

Is Human-Monkey Embryo Combination OK?