A mouse that can speak? A monkey with Down's Syndrome? Dogs with human hands or feet? British scientists want to know if such experiments are acceptable, or if they go too far in the name of medical research.

To find out, Britain's Academy of Medical Sciences launched a study Tuesday to look at the use of animals containing human material in scientific research.
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Using human material in animals is not new. Scientists have already created rhesus macaque monkeys that have a human form of the Huntingdon's gene so they can investigate how the disease develops; and mice with livers made from human cells are being used to study the effects of new drugs.

But scientists say the technology to put ever greater amounts of human genetic material into animals is spreading quickly around the world -- raising the possibility that some scientists in some places may want to push boundaries.

"There is a whole raft of new scientific techniques that will make it not only easier but also more important to be able to do these cross-species experiments," Bobrow said.
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Bobrow said there was a "sort of understanding" within the scientific community that "as you get close to 50/50 mix" of human and animal material, the boundaries are near, but he said laws were vague at best.

"Do most of us care if we make a mouse whose blood cells or liver are human? Probably not," he said. "But if it can speak? If it can think? Or if it is conscious in a human way? Then we're in a completely different ballpark."

British lawmakers voted to legalize the creation of animal-human embryos for medical research. In the future, scientists in Britain will be allowed to combine human DNA with animal egg cells. But the law says the resulting "chimera" embryos must destroyed within 14 days, and cannot be implanted. From [here]

By that logic, Cornelius, do we deserve it now? You've put "deserved" in past tense, y'see. And if we deserve it now, then it would seem we've already gone too far.

The target of Geschwind’s analysis was FOXP2, a gene that rose to scientific prominence during the study of a London-based family afflicted by hereditary speech disorders. Of the extended family’s 30 members, one-half have severe linguistic deficiencies, as well as a FOXP2 mutation. Those who don’t have the mutation are able to speak normally.