“Cloning describes the process used to create an exact genetic replica of another cell, tissue or organism,” according to MedlinePlus. The clone is the copied material, which has the same genetic built as the original. The gene is the basic unit of genetic material.
The genetic instructions inside the living cell are called deoxyribonucleic acid, or DNA. Researchers have cloned whole organisms and biological materials. Researchers use different kinds of techniques to make gene copies. The procedure starts with inserting a gene from a certain organism, this is called “foreign DNA” into genetic material or a carrier, called the vector. A vector could be something like a bacteria cell or virus. Once the gene has been inserted, it is placed in laboratory conditions, which causes it to multiply. This results in the gene being copied many times over. There are three different kinds of artificial cloning; gene cloning, reproductive cloning, and therapeutic cloning.
Gene cloning, or DNA cloning, is very different from reproductive and therapeutic cloning. Gene cloning produces the copies or sections of DNA. Reproductive cloning creates copies of whole animals or humans. Therapeutic cloning produces embryonic stem cells for experiments targeted towards creating tissues to replace injured or diseased tissues, according to the National Humans Research Genome Research Institute. Reproductive and therapeutic cloning are used for different purposes, but share a lot of techniques. The first mammal was cloned in 1997 which led many people to think it wouldn’t be long until scientist would be able to clone humans. Immediately after, a council on bioethics and an emergency report both published reports claiming that the technology was unsafe and dangerous, and that it should be banned, even for scientific research. There is currently no information on anyone successfully cloning a human embryo, but there have been many claims that a human has been cloned, but no evidence of it.
Cloning humans are actually much more difficult than cloning mammals. This is because two proteins called spindle proteins, that are essential to cell division, are located very close to the chromosome in primate eggs. Because of this, the removal of the egg’s nucleus to make room for the donor nucleus, also removes the spindle proteins, interfering with cell division. In other mammals, the two spindle fibers are more spread out and not located as close to the chromosomes. So during removal of the egg’s nucleus, there is no loss of spindle fibers. There are many pros and cons to cloning humans. A pro to cloning humans would be that it could eliminate defective genes. When humans reproduce there is an increase in damage to their DNA lines, which creates defective and mutated genes. These genes could be terminated by cloning healthy human cells.
Usage of Cloning
Another pro is that cloning technology can potentially cure some disorders. This can be done by replacing damaged tissues or organs within the body because the transplanting process could become much simpler. Along with cloning humans, there are also many cons, one major example is that it interferes with nature. Another con of cloning humans is that it could easily decrease the value of human life significantly and cloning humans operates against many religious ethics. A group of animals that have vertebrates, higher animals, consist of billions of cells. Almost all of these cells have a nucleus, which contains genetic information in the form of DNA. The information is the exact same for every cell in the animal. Scientists use the Nuclear Transfer technique to clone animals. Scientists start by removing the nucleus from a cell, this nucleus is called the donor nucleus. Scientists then put the donor nucleus into an egg cell from the species whose nucleus has been destroyed. The egg cell now has a new nucleus and the same genetic makeup as the donor animal. Once the egg has a new nucleus, the cell must be activated to create the embryo. An embryo is a mass of cells that can grow into a fully formed organism, according to World Book Student. To activate the cell, scientists normally give the cell a small electric shock.
Next the DNA of the donor egg must be reprogrammed by the egg. When scientist reprogram the DNA, they are activating part of the DNA not active in the parent cell. This allows the cell to develop into an entire organism instead of just a copy of the donor cell. Scientists do not fully understand how the egg can reprogram such like this, yet programming techniques like these have a very high failure rate. These experiments often result in the death of the cloned embryo and sometimes scientists even place the cloned embryo into the womb of a substitute mother, who carries the clone until birth. Scientist were already cloning amphibians in the 50’s such as frogs and salamanders. The first mammal cloned was in 1996 by a British team led by Ian Wilmut. It was a sheep named Dolly. Since this sheep was cloned, many other countries have used similar techniques to clone mice, cats, and cows. Some cons to cloning animals are that cloning animals have a very low success rate, actually, 95% of cloning attempts end in failure. Cloning attempts also have a high rate of many birth defects or illnesses.
Cloning is also the least reliable way of reproduction and another con is that cloning is very, very expensive. Along with cons, there are a couple pros to cloning animals. One would be that it would help to restore species that are going extinct, which could help certain ecosystems survive longer, but this would majorly affect “the circle of life”. There are many ethnic concerns to cloning animals and humans and for many different reasons. Cloning experiments have given scientists a lot of information on biological processes, that could be used to develop treatments for many diseases.
Scientists have still not perfected a technique used to clone mammals, and still, find it difficult to consistently produce healthy clones. Most cloned embryos do not even make it to birth, and cloned animals have a much higher chance of being born with birth defects than naturally produced animals. Cloning is the process of making an exact copy of someone or something. There are three different kinds of cloning, gene cloning, reproductive cloning, and therapeutic cloning. Cloning a human embryo has been attempted at many time but never successfully. Many pros and cons to both forms of cloning prove that cloning can be taken as ethical or unethical, depending on Geib, Claudia.
- “We’re Getting Closer to Cloning Humans. Here’s What’s Stopping Us.” Futurism, Futurism, 16 Apr. 2018, futurism.com/human-cloning-whats-stopping.
- “Cloning Fact Sheet.” National Human Genome Research Institute (NHGRI), 21 Mar. 2017, www.genome.gov/25020028/cloning-fact-sheet/.
- Seidel, George E., Jr. ‘Cloning.’ World Book Student, World Book, 2018, www.worldbookonline.com/student-new/#/article/home/ar 119610. Accessed 15 Oct. 2018. What Is Cloning, learn.genetics.utah.edu/content/cloning/whatiscloning/.
- Office of the Commissioner. “Consumer Updates – Animal Cloning and Food Safety.” U S Food and Drug Administration Home Page, Office of the Commissioner, www.fda.gov/ForConsumers/ConsumerUpdates/ucm148768.htm.