Cloning is a process used to obtain an identical organism asexually. The clone it produces does not only look and think like its donor, its DNA is identical. DNA stands for deoxyribonucleic acid. It is the substance which contains the genetic information for most organisms. In other words, it contains the information that tells the body how to work and develop. For example, if you have blue eyes, it is a result of your DNA.
The technique that makes cloning possible is nuclear transfer. It was first explored in the 1920s by Hans Spemann for the purpose of conducting genetics research, the study of heredity and genes in living organisms. It is still used in every true cloning laboratory around the world, and every cloning experiment involving adult mammals has employed it. Another similar technique, dubbed "twinning", is used as well, but it should not be confused with cloning and nuclear transfer, because it is simply the act of splitting the cells of a young embryo. It is basically the same idea as having twins.
Nuclear transfer requires two cells, a donor cell and an oocyte, or egg cell. Contrary to previous belief, research has proven that the egg cell works optimally if it is unfertilized. First, the egg cell must be enucleated. This means that the nucleus is removed from the cell. Since the majority of its genetic information is stored in the nucleus, this eliminates the cell's heritage. The donor cell is then forced into a stage called the Gap Zero (sometimes referred to as G0 stage; another stage of cell dormancy is Gap One, or G1, etc.), a dormant phase. This is done in different ways, depending on the technique. This Gap Zero stage causes the cell to shut down, but it does not die.
Now, the nucleus of the donor cell is ready to be accepted by the egg cell, which at this point does not have one. The donor cell's nucleus is then removed from the donor cell and placed inside the egg cell. This feat is accomplished either through cell fusion or transplantation. The egg cell is then prompted to begin forming an embryo, either by an electric pulse or by the effects of a chemical culture. Once this happens, the embryo can be transplanted into a surrogate mother, an animal used to carry and give birth to embryos which are not its own. If all goes well and with a little luck, the surrogate mother will give birth to a perfect replica of the donor animal.
Scientists have studied and experimented with cloning. The first to do so was an Austrian monk named Gregor Johann Mendel. He studied the pea plants in his garden at the monastery over a century and a half ago. He began experimentation in 1856, and eight years later, he established the basic laws of heredity. He observed that specific characteristics of the plants [such as height and color] were passed from parent plants to new plants. Mendel assumed the appearance of a characteristic was controlled by a pair of factors, one factor from each parent. (Hyde, 26) Now these factors are called genes. Mendel was important to the world of genetics because before his discovery, ideas about heredity were based on speculation and superstition.
Dr. Steen Willadsen, a cloning expert and pioneer, developed the modern fundamental methods for the cloning of animals. He says, "From my perspective, it's just a matter of time [before the first human is cloned]," Willadsen said he had no moral issues with cloning. "It is not for me, as a person who invents techniques, to say how we should use them," he also said. (Kolata.)
Lori Andrews, a professor at the Chicago-Kent College of Law and an expert on legal issues of reproduction, said that she recently received a call from a British scientist who agreed with Willadsen's point of view. She also stated that another doctor told her that, "If any of my relatives got cancer, I would clone them," and then use the clone as a bone marrow donor to save the cancer victim's life. "I absolutely think the tenor has changed," said Ms. Andrews. "People who said that human cloning would never be done are now saying, 'Well, the risks aren't all that great'." She also said that, "Unless I see a total shift in the burden of proof saying that unless you can prove there is actually going to be harm, then we should allow human cloning." (Kolata.)
Three decades ago, two fertility experts, Dr. Sophia Kleegman and Dr. Sherwin Kaufman, wrote that new productive arrangements pass through several predictable stages. These begin with "horrified negation" to "slow and gradual curiosity, study and evaluation", and finally, end with a "very slow but steady acceptance". (Kolata.)
Scientists say an extremely beneficial side effect of cloning is to make it possible for the first time to seriously consider genetically enhancing human beings (To give a human special characteristics or traits that would not otherwise be found in that human being.) . Dr. Lee Silver, who is a molecular biologist at Princeton University, has thoroughly predicted these benefits. He says, "In a sense it would be no differently morally from vaccinating a child for a disease." (Kolata.)
Dr. James Grifo, the director of the Division of Reproductive Endocrinology at New York University Medical Center, is working on nuclear transfer in humans. His goal is to use cloning to help older women have children; this makes it apparent that he is in support of human cloning.
Dr. Donald Wolf, a senior scientist at the University of Oregon, and his team have two federal grants to study cloning in monkeys. One involves cloning from a human adult. This makes it obvious where the government wishes to be heading with human cloning. "We're pretty optimistic," Wolf says, "We have every reason to believe it will work."
The first clone was generated in 1958 by F. C Steward, who was a that time the director of the Laboratory for Cell Physiology, Growth, and Development at Cornell University. He was able to clone carrots from cells in the roots. He put the cells in a nutrient solution, and they began to grow into new roots. Today, his methods seem primitive, but they were effective enough to make him famous in the world of engineered reproduction. Since the 1950s, his techniques have expanded, and now just about every plant can be cloned with relative ease.
There are two main techniques for the cloning of animals: the Roslin technique and the Honolulu technique. The Roslin technique was developed by Ian Wilmut and his colleagues at the Roslin Institute in Scotland. Wilmut can be considered a cloning pioneer in a sense because he created the cloned sheep Dolly and the transgenic clone Polly.
Dolly hit the headlines enormously. She caused a huge uproar among the public as well as the scientific community. To the public, she was a surprise because no one had really heard any big news about the genetical engineering field in some time, and no one had prepared them for a cloned animal that everyone could relate to. In the scientific community, the stir was, on the other hand, about the fact that Dolly had been created from the cells of a six-year old ewe. According to conventional wisdom, adult cells cannot give rise to new, mature organisms. (http://www.sciencemag.org/cgi/content/full/278/5346/2038.) Dolly broke the rules, so after her debut, scientists and researchers scrambled to understand how she was created. They found out that Dolly was a real clone, and truly had been cloned from mature cells. This new development has brought about a significant change in the genetics field, because now clones can come from any organism, endlessly widening the usage field of cloning.