Several animal species have already been genetically modified, and at least eleven have been cloned, though some scientists doubt the health of those clones that survived to birth.
Some of these efforts are commercial, either for agribusiness or for sale directly to consumers as pets. Others are scientific experiments, usually defended as advancing, directly or indirectly, the cause of medicine for humans.
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The Roslin Institute, where the first mammal was cloned, maintains records of all published mammalian cloning experiments up to July 2002 - 50 papers detailing 68 experiments, with 386 surviving clones. They conclude that the "overall efficiency of cloning is typically between 0 and 3% (number of live offspring as a percentage of the number of nuclear transfer embryos), irrespective of the species, the donor cell type or technique." There is no evidence that efficiency has significantly improved since.
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"Pharming"
Cattle, sheep, goats, chickens, rabbits and pigs have been genetically modified with the aim of producing human proteins that are useful, generally as medicines. The gene transfer process is typically very inefficient, and cloning is seen as another way of propagating the GM animal.
A 1999 USDA report cited estimates that there was a $24 billion market for human proteins, and theoretically 600 transgenic cows could supply the worldwide demands for some drugs. In practice, however, several companies that have pursued this line have gone bust, and the profit potential seems less than it once did.
Genetic modification of animals in order to improve the prospects of organ transplants is also being investigated.
I wish!
