Publication of the chimp genome has highlighted the confusion surrounding our relationship to the great apes. And is reliable lie detection now possible?by Philip Ball / October 22, 2005 / Leave a comment
Published in October 2005 issue of Prospect Magazine
How close are we to the chimps?
Clint is dead, but his genome lives on. DNA donors for animal genome projects aren’t usually given names, but Clint was an exception. He was a chimpanzee, and the publication of his genome at the beginning of September has highlighted the confusion that exists about our relationship with—and responsibilities towards—chimps and other great apes.
One viewpoint holds that experiments on chimps are vital for the development of urgently needed new drugs. Chimpanzees are the only animals that can be successfully infected with the Aids virus and with hepatitis B and C, and they suffer from their own forms of malaria parasite. So they are pretty much irreplaceable in testing new therapies for these diseases.
Yet the US is the only developed country apart from Japan (where a ban has been mooted) that uses chimps in biomedical research. Even there, a moratorium has been imposed since 1997 on the breeding of chimps for research at the National Institutes of Health, the US equivalent of the Medical Research Council. And some US researchers have argued that ethical restrictions on such research should be tightened to make them broadly the same as those for human subjects who cannot give informed consent. They include archiving all tissue samples and identifying each animal by a name.
But just how closely related are human beings and chimps? That is one of the issues the genome sequence will address. A 98 per cent genetic similarity between the two species is commonly quoted, but the precise figure remains uncertain. In any event, these numbers highlight the dangerous, reductive simplification that genome studies encourage. There are genetic differences between individuals and between different populations of chimps, just as there are in human beings, and in any case an organism’s genetic make-up is not only a question of which genes they have, but also how they are used.