Cloned monkeys spur warnings against human cloning
SHANGHAI (BP) -- The first-ever primates cloned through a technique that produced Dolly the sheep have been cited by Christian bioethicists as a potentially valuable development in animal research. But they warned that two monkeys engineered by Chinese researchers must not become a step toward cloning humans.
"While lauded as a valuable scientific breakthrough," Johnson, pastor of The Journey Church in West Chester, Pa., told Baptist Press, "even a quiet inference fortified by this experiment that human life is merely the result of cellular manipulation brings our culture ever closer to the slippery slope of crucial ethical and eugenic dilemmas."
Researchers from the Chinese Academy of Sciences Institute of Neuroscience announced in a Jan. 24 article for the journal Cell that they produced two genetically-identical long-tailed macaque monkeys using a scientific technique known as somatic cell nuclear transfer (SCNT).
The technique -- which produced Dolly, the world's first cloned mammal, in 1996 -- involves removing an egg's nucleus and replacing it with a nucleus from another cell, replete with genetic material. The egg then is stimulated to develop into an embryo and implanted in a surrogate mother.
Using a tweaked version of SCNT, the Chinese team discovered cells from aborted monkey fetuses worked better than adult cells for providing genetic material.
Some 181 embryos cloned from adult monkey cells were implanted in 42 surrogates, yielding two live births, neither of which survived beyond 30 hours, the researchers wrote. However, 79 embryos cloned using fetal cells were implanted into 21 surrogate mothers and yielded two live births. Both infant monkeys seemed to develop normally.
They were named Hua Hua and Zhong Zhong -- derived, according to CNN, from the Chinese word Zhonghua, meaning "Chinese nation."
Union University bioethicist C. Ben Mitchell told BP attempts to clone humans using the version of SCNT pioneered by the Chinese team would violate biblical standards by, among other sins, destroying unborn humans in the cloning process.
"Human cloning cannot pass ethical muster," said Mitchell, editor of the journal Ethics & Medicine. "The potential risks to unborn human life cannot be justified."
In addition, health problems experienced by previous animal clones should yield caution in future cloning experiments, Mitchell said.
Dolly died at age 6 in 2003 with signs of advanced aging despite being well shy of the 11- to 12-year lifespan some sheep experience, BP reported at the time.
"Dolly was not a healthy sheep," Mitchell said in written comments. "She had a number of anomalies that made her life less than ideal."
Hua Hua and Zhong Zhong seem to be developing normally and will continue to be evaluated as they age, CNN reported.
The Chinese team said it has no intention of cloning humans, according to USA Today.
The researchers wrote in Cell that cloned primates "are ideal animal models for studying physiological functions unique to primates and for developing therapeutic treatments of human diseases."
Yet even with animal experimentation, Mitchell said, there are ethical limits.
"Animal cloning is subject to the same ethical standards as other animal experimentation," Mitchell said. "There is no need to inflict unnecessary suffering on animals."
Including Dolly, 23 species of mammals have been cloned using SCNT, the Chinese researchers noted. Primates have been cloned previously using a simpler method, according to media reports.