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Cloning: What's Stopping us? Science (Part 1 of 3) Ivanhoe Broadcast News Last Updated: October 04, 2004 ORLANDO, Fla. (Ivanhoe Broadcast News) -- By definition, cloning is an exact genetic replica of a DNA molecule, cell, tissue, organ or entire animal. There are two types of cloning -- therapeutic, which could replace diseased tissues and reproductive cloning, which is the cloning of an entire human being. Reproductive cloning is far more controversial. Putting aside the ethical issues, here's a look at the science behind it all. At 43, Liz Catalan knows she's running out of time to be a mom. She's been struggling with infertility since her wedding day. "I was going to have 4, 5, 6 children," she tells Ivanhoe. "Both my husband and I thought that, but unfortunately that did not work out that way." She says holidays with nieces and nephews are tough. "Sometimes you know, you'll sit in the corner and you'll be thinking, you know, 'How about me?' I don't have my child." Fertility treatments have failed. She won't rule out adoption, but Catalan still wants her own biological child -- even if that means cloning. It's something that has not been done in humans -- yet. "If you try hard enough, all species will be able to be cloned," scientist Jose Cibelli, Ph.D., tells Ivanhoe. Cibelli, a professor of animal biotechnology at Michigan State University in Lansing, says cloning uses the same technology for all species. Sheep, cows, pigs, even horses have been cloned. And in February 2004, scientists from South Korea cloned the first human embryo. They did not implant it in a woman, but they could have. Proof that scientifically, human cloning is possible. But based on animal research, it's a risky step. "If you want to make a cloned cow, you have to transfer about 10 recipient cows with cloned embryos in them to get one healthy animal on the ground," Cibelli says. Yet there are problems before you even get to that point. Cibelli estimates if scientists start with 100 cow eggs, 30 will die in the petri dish. Of those remaining 70, only about 15 eggs could be transferred to seven cows. Four of those seven cows might get pregnant. Two fetuses would die early in the pregnancy. One would die just before birth. That leaves just one surviving clone. Of those few that make it, many will have under-developed lungs or immune system failure. All this has caused even the most forward-thinking scientists to question human cloning. Even Cibelli says it is completely unsafe at the moment. "Whoever wants to attempt it is a criminal and should be penalized." But animal cloning is progressing. At the Audubon Nature Institute in New Orleans, Betsy Dresser, Ph.D., cloned African wildcats -- the first in the world. "My personal hope for cloning is that it becomes one of the tools that we can call on when we have a species that drops so low in number," Dresser tells Ivanhoe. During the process at the Audubon Nature Institute, surgeons extract eggs from a housecat. They remove the DNA and inject cells from a wildcat into those empty eggs, which are re-implanted into the housecat. Nine weeks later, a wildcat clone is born. As the research moves forward, the failure rate is likely to decrease. If that happens, human cloning may gain more support. Cibelli says, "In the future, if we can guarantee that this is safe, I will have to rethink my views on it, but it will take a long, long time to make this safe." It's that small chance that Catalan is holding onto. "I will wait as long as I have to," she says. And as with most scientific breakthroughs, time is often all it takes. This article was reported by Ivanhoe.com, who offers Medical Alerts by e-mail every day of the week. To subscribe, go to: http://www.ivanhoe.com/newsalert/. If you would like more information, please contact: Jose Cibelli, Ph.D. Michigan State University Lansing, MI (517) 432-9206 [log in to unmask] Last Updated: October 04, 2004 SOURCE: HealthCentral.com http://www.healthcentral.com/news/NewsFullText.cfm?id=8009645 * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn