But why would we want to? Below are some of the ways in which cloning might be useful. Cloning for medical purposes has the potential to benefit large numbers of people.
How might cloning be used in medicine? Much of what researchers learn about human disease comes from studying animal models such as mice. Often, animal models are genetically engineered to carry disease-causing mutations in their genes. Creating these transgenic animals is a time-intensive process that requires trial-and-error and several generations of breeding. Cloning could help reduce the time needed to make a transgenic animal model, and the result would be a population of genetically identical animals for study.
Stem cells build, maintain, and repair the body throughout our lives. Because these are processes that stem cells do naturally, they can be manipulated to repair damaged or diseased organs and tissues.
But stem cells transferred from one person to another such as in a bone marrow transplant are seen as foreign, and they usually trigger an immune response. Some researchers are looking at cloning as a way to create stem cells that are genetically identical to an individual.
These cells could then be used for medical purposes, possibly even for growing whole organs. And stem cells cloned from someone with a disease could be grown in culture and studied to help researchers understand the disease and develop treatments.
In , scientists at Oregon Health and Science University were the first to use cloning techniques to successfully create human embryonic stem cells.
The donor DNA came from an 8-month-old with a rare genetic disease. You might have seen the Jurassic Park movies. In the original feature film, based on the Michael Crichton novel, scientists use DNA preserved for tens of millions of years to clone dinosaurs.
They run into trouble, however, when they realize that the cloned creatures were smarter and fiercer than expected. Could we really clone dinosaurs? In theory? You would need: A well-preserved source of DNA from the extinct dinosaur, and A closely related species, currently living, that could serve as an egg donor and surrogate mother. It's extremely unlikely that dinosaur DNA could survive undamaged for such a long time.
However, scientists have been working to clone species that became extinct more recently, using DNA from well-preserved tissue samples. A number of projects are underway to clone extinct species, including the wooly mammoth. In , scientists had their first near-success resurrecting an extinct animal.
Using goats as egg donors and surrogates, they made several clones of a wild mountain goat called the bucardo—but the longest-surviving clone died soon after birth. Even if the effort eventually succeeds, the only frozen tissue sample comes from a female, so it will only produce female clones.
However, scientists speculate they may beable to remove one X chromosome and add a Y chromosome from a related goat species to make a male. Cloning endangered species is much easier, mainly because the surviving animals can donate healthy, living cells.
In fact, several wild species have been cloned already, including two relatives of cattle called the guar and the banteng, mouflon sheep, deer, bison, and coyotes.
However, some experts are skeptical that cloning can help a species recover. One big challenge endangered species face is the loss of genetic diversity, and cloning does nothing to address this problem. When a species has high genetic diversity, there is a better chance that some individuals would have genetic variations that could help them survive an environmental challenge such as an infectious disease. Cloning also does not address the problems that put the species in danger in the first place, such as habitat destruction and hunting.
But cloning may be one more tool that conservation scientists can add to their toolbox. Left: the alpine ibex, a close cousin of the Bucardo. Right: the last remaining Bucardo with the research team before her eventual death.
She was blindfolded to shield her eyes from the photographer's flash. So reproductive human cloning is unethical and has no laws surrounding it but only a ban that prohibits the practice of such science.
Therapeutic cloning allows us to create tissue from the nucleus of a cell and use its genetic material and information to replicate it.
Think about the possibilities cloning could bring. Organs on hand for people who are in need, same with blood, plasma, and skin damage. I think this similar to the stem-cell research debate. The question is what do you consider life. If cloning technology is possible, what if we clone bodies with no higher functions.
Although this is still theoretical, it keeps the debate about what specifically defines life going. A lot of misinformation is spread about stem cells which I think is the biggest issue in making it a more widely spread form of treatment. Linked below is some basic information about stem cells.
In some sense , I feel it depends on a lot of things that would make me consider whether or not cloning is good or bad. In the religious community, it can be seen as playing god. With me, if its in the name of bettering human kind, thats fine by me. Here is a site my buddy pointed out to me that covered some of his thoughts on cloning. The idea of cloning was something I became very interested in as a child from watching a lot of action and sci-fi movies.
While the idea seems very cool in theory, or when it is exaggerated on the big screen, I cannot get behind cloning because of the ethical problems. There are still big health concerns with whether or not abnormalities would show up in humans. This article from global change does a great job going over the three risks you would face with mutation of genes, emotional risks, and how people would abuse cloning technology.
Some researchers have reported that the cells of cloned animals appear to have shorter telomeres — snippets of DNA at the ends of chromosomes that have been linked to the cellular aging process. Why would anyone want a cloned baby? The organization says other clients are trying to have babies who will genetically match children they have lost.
The Raelians, meanwhile, believe that humans could achieve a kind of immortality by cloning themselves, then somehow transferring their consciousness from one generation to the next.
Is the U. The House passed proposed legislation last year aimed at banning therapeutic as well as reproductive human cloning, but the measure was stalled in the Democratic-led Senate. The Senate is now coming under Republican control, however, and the new majority leader is Bill Frist, a Tennessee physician opposed to both varieties of human cloning. Observers on both sides of the cloning issue expect a renewed political push for anti-cloning legislation during the next congressional session.
Is anyone else trying to clone humans? Italian fertility doctor Severino Antinori predicts that his separate project will result in the birth of a cloned baby boy in January.
Advanced Cell Technology, the Massachusetts-based company where Lanza does his research, has been the only U. A number of laboratories outside the United States are involved in therapeutic human cloning research, sparking concerns among some scientists that U. Several countries, including Britain, have established laws that outlaw reproductive human cloning while allowing therapeutic cloning.
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