Duke Research On Cloning Suggests It May Be Easier In Humans Than Animals
Posted August 16, 2001 10:41 a.m. EDT
DURHAM — According to a study published in the latest issue of Human Molecular Genetics, scientists at Duke University say cloning humans would be easier than most animals.
The study shows a genetic benefit that protects humans from problems found in cloned animals like sheep.
"Our lab doesn't clone anything, and doesn't plan to clone anything," said Dr. Randy Jirtle.
Jirtle and his colleagues at Duke are interested in gene function for the purpose of cancer research. But what they found adds fuel to the fiery debate over human cloning.
The research study shows that a specific gene labeled IFG2R is different in humans as compared to non-primate mammals like sheep and mice. Those animals only inherit one IFG2R gene from their parents, but humans get two. That gene controls fetal growth and inhibits disease, problems commonly found in cloning experiments.
"We have two functional copies, so we are intrinsically more resistant to cancer formation, for example, than mice are," said Jirtle.
And, Jirtle says, the gene in non-primate mammals is imprinted like a computer program that automatically turns off the gene's function.
"And because of it being imprinted, the only functional copy gets turned off during cloning. And now you have no brakes. It's like that one prop engine going down and the animals get large," said Jirtle.
The research suggests that human cloning without that genetic problem would be easier than with sheep and mice.
"So the success rate should increase," said Jirtle.
But not necessarily without some failed attempts.
Dr. Jirtle believes the research findings may change the human cloning debate hanging the question of can it be done, to should it be done.
The research also suggests that many disease-treating drugs abandoned because they caused cancer in lab mice, may need to be retested in primates, closer in genetic similarity to humans.