Cloning

A

Benefits of Animal Cloning

Despite these drawbacks, scientists believe that animal cloning will one day advance agricultural practices and medicine, and even prevent the extinction of endangered animals. In agriculture, cloned cattle could produce a higher yield of meat or milk. The pharmaceutical industry already uses cloned animals to produce drugs for human use. For example, PPL Therapeutics in Scotland has generated sheep that produce milk containing a protein that helps in the treatment of hemophilia. One day pharmaceutical firms may clone large populations of genetically modified animals to quickly and inexpensively derive this protein for use in drug products.

Cloned animals could also improve laboratory experiments. Researchers could create many genetically identical animals to reduce the variability in a sample population used in experiments, making it easier for scientists to evaluate disease. Moreover, scientists could clone a large number of animals that suffer from a human disease, such as arthritis, to study the disease’s progression and potential treatments. Some cloned animals such as sheep and pigs live for years, and scientists could use these animals to evaluate their long-term response to drug treatments.

B

Cloning Endangered and Extinct Animals

Cloning may bring some animal populations back from the brink of extinction. In 2001 scientists successfully cloned a gaur, an endangered ox that lives in Southeast Asia. Scientists inserted the genetic material from the skin cell of a dead male gaur into a cow’s egg cell that had its nucleus removed. The resulting embryo was then implanted into a female cow, which served as the surrogate mother. The gaur calf died two days after birth from a bacterial infection apparently unrelated to the cloning process. Also in 2001 scientists cloned the mouflon, an endangered sheep from Sardinia, Corsica, and Cyprus. Teams of scientists also hope to clone other endangered animals, including the African bongo antelope, Sumatran tiger, and giant panda.

Scientists may one day clone extinct animals. The last wild Spanish ibex, also known as bucardo, a mountain goat native to the Pyrenees mountain range of northern Spain, died in 2000. Spanish scientists preserved some of its cells, hoping to use the cells to create a cloned embryo and then implant the embryo into a more common type of goat with a genetic makeup similar to that of the Spanish ibex.

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In order for scientists to clone endangered and extinct animals, however, they need cells containing an intact nucleus with undamaged DNA. They also need to implant a cloned embryo into a surrogate mother from a closely related species. These requirements prevent scientists from cloning cells from the fossilized remains of dinosaurs and other long-extinct animals.

C

Can Humans Be Cloned?

If scientists can clone animals, can they clone humans? In 1998 a South Korean research team announced that it cloned a human embryo through somatic cell nuclear transfer, but the embryo only survived to four cells. In 2001 researchers at the biotechnology firm Advanced Cell Technology claimed to clone human embryos that divided to six cells before dying. Many scientists argue that because the embryos from these two experiments did not double their cell size every 24 hours, they could not be considered true human embryos.

In 2004 a team of South Korean researchers, led by Woo Suk Hwang of Seoul National University, announced that they had cloned human embryos capable of reaching the blastocyst stage and had succeeded in extracting stem cells from one of the embryos. However, a university panel later determined that Hwang’s research was fabricated. Hwang resigned his position from the university. Many observers believed that stem cell research was likely to receive a major setback in funding as a result of the fraud.

Although the research was fabricated, it still raised a number of ethical issues. To some people it is ethically unacceptable to destroy a human embryo for any reason. To others it is acceptable to do so if there is the prospect of understanding and treating human diseases. The production of embryos using the cloning method offers specific advantages. Embryonic stem cells could be matched to a patient so that tissues or organs developed from the embryo would be recognized by the patient’s immune system. Otherwise, the patient’s immune system would reject any foreign tissue or organs, or the patient would have to take drugs to suppress the immune system, which could lead to infections.

However, this cloning procedure could be used to produce children who would be genetically identical to the person who donated the embryonic stem cell. A great majority of people would find this totally unacceptable. To many people it is important to draw a distinction between cloning to derive cells for therapeutic treatment and cloning to produce a child.

VII

Why Cloning Is Controversial

New areas of science often raise questions about safety. Early experiments in animal cloning attracted attention over its potential dangers. In some experiments in the early 1990s, for example, cloned cows developed faulty immune systems. Other projects created cloned mice that grew obese. In some studies, cloned animals seemed to grow old faster and die younger than normal members of the species.

In 2002 the National Academy of Sciences released a report calling for a legal ban on human cloning. The report concluded that the high rate of health problems in cloned animals indicates that such an effort in humans would be highly dangerous for the mother and developing embryo and is likely to fail.

Beyond safety, the possibility of cloning humans also raises a variety of social issues. What psychological issues would result for a cloned child who is the identical twin of his or her parent? How will a cloned child deal with the pressures of being compared to its genetic donor? A clone will never be identical to the genetic donor because environmental differences will influence the clone’s development. Still, a cloned boy created from basketball star Michael Jordan’s genetic material, for example, could suffer considerable criticism if he decided to pursue classical piano instead of slam-dunking.

Are these issues compelling enough to ban the cloning of humans? Although some scholars argue that a clone might face unique problems, most offspring face some sort of burden. Children from poor families, for example, suffer some hardships that children from wealthy homes never imagine. Children in some developing nations face a tougher life than children in the United States. Nevertheless, few people would encourage a ban against having babies because of financial status or where a person lives. Cloning proponents argue that human cloning should not be banned simply because of potential hardships for the offspring.

If human cloning ever becomes an option for parents, financial status could play a role because cloning would probably be expensive and only available to the wealthy. Accordingly, wealthy families might use cloning to give their offspring the best characteristics imaginable. Scientists could use genetic engineering to put together genes for such characteristics as beauty or intelligence, and then clone the cell to make a super child of sorts. If that capability was only available to wealthy people, the divide between the wealthy and the poor could widen farther than ever imagined.

Soon after the cloning of the first human embryos in 2001, the Roman Catholic Church condemned such research. Many other religions agree that human cloning should be entirely and forever banned. Theologians view cloning as a thorny issue, an example of the ongoing tension between faith and science. Some people believe the scientific advances that enable human cloning are a God-given blessing. Others argue that scientists should not presume to play God by manipulating human genetic makeup. Some opponents claim that cloning must be forbidden because it involves destroying human embryos—such as the ones used to harvest stem cells. These opponents argue that any embryo is a viable human being and should never be destroyed intentionally.

The research of the South Korean scientists in 2004, for example, came under criticism for precisely this reason. In order to extract stem cells from one of the cloned embryos, the embryo had to be destroyed. The South Korean research was also criticized because the female volunteers who donated their egg cells were given risky fertility drugs.

VIII

Regulation of Cloning

These religious viewpoints, however, do not end the discussion over whether banning is right or wrong, good or bad. In all likelihood, the future of cloning in the United States and in other nations will depend on political actions. For instance, in August 2001 President George W. Bush used his executive powers to ban the use of federal funds for research on new stem cells derived from human embryos. This ban halted federally funded scientists from cloning new human stem cells from embryos, but it allowed them to continue using stem cells already developed. This ban did not prevent privately funded scientists from pursuing research on embryonic stem cells from humans.

While Bush’s policy dictated how government money would be spent on stem cell research, in the United States no federal legislation exists that regulates cloning, although a number of bills that restrict or ban cloning have been introduced to Congress. For example, in July 2001 the U.S. House of Representatives voted in favor of a bill outlawing any sort of human cloning. According to this bill, any scientist participating in human cloning—whether federally or privately funded—would face ten years in prison and a $1-million fine. This bill would also make it illegal to import any product developed from human cloning. In other words, even if scientists in another country developed a wonder drug through a process that involved human cloning, it could not be used in the United States. A similar bill passed the House in 2003. Both bills, however, failed to pass the Senate where there is support for the use of cloned stem cells in research or therapy.

Other nations have sought to regulate human cloning, with varying degrees of restriction. France and Italy have banned human cloning altogether, and Russia’s government approved a five-year moratorium on all human cloning research in 2001. The United Kingdom passed the Human Reproductive Cloning Bill in 2001, which “prohibits the placing in a woman of a human embryo which has been created otherwise than by fertilization.” But British law permits scientists to create human embryos for research purposes. In Australia, the Gene Technology Act 2000 prohibits trying to clone humans or make human-animal hybrids. Many countries have yet to create laws against human cloning. Canada’s government, for example, has tried twice to pass a law against human cloning, but both attempts failed.

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