Clones are genetically identical copies of a living organism. The clones have the same genetic makeup as the original. Clones occur in nature via asexual reproduction and with the help of scientific advancement humans have succeeded in creating clones in the lab artificially. Humans have created clones of genes, cells, tissues, organs, and even an entire organism via artificial cloning. Dolly, the first cloned mammal, is an example of successful artificial cloning. Since then, scientists have been continuously working towards perfecting their cloning technology and have presented an array of cloned animals to the world. The first lab-cloned plant was a carrot (cloned in 1958), and the first artificially cloned animal was a toad (created in 1964). Modern artificial cloning has reached an advanced stage with the implementation of biotechnological techniques, including cellular cloning (single-cell cloning), molecular or gene cloning (producing copies of genes or segments of DNA), reproductive cloning (producing copies of whole animals via somatic cell nuclear transfer), and therapeutic cloning (producing embryonic stem cells to replace damaged tissues). Let’s take a look at some of the prominent cloning examples in real life.
Bacteria create self-copies or reproduce asexually through binary fission, budding, cysts, endospores, and conidia formation. This is an example of natural cloning.
Fungi reproduce asexually by fragmentation, budding, or producing spores. The most commonly known fungi species are baker’s yeast, bread molds, sac fungi, Mycorrhizae, and common edible mushrooms. This is an example of natural cloning.
If you take a sample from any natural water source and observe it under a microscope, it is highly likely that you will find protists floating around. Protists are considered the first eukaryotic organisms that inhabited the earth before plants, animals, or fungi. Protists reproduce through binary fission (division of one nucleus), multiple fission (division of many nuclei), and budding. Amoeba, Paramecium, Euglena, Plasmodium, and slime molds are some of the widely known protists that are natural cloning examples in real life. This is an example of natural cloning.
4. Plants (Natural Cloning)
Plants are one of the most evident examples of natural cloning. Some plants reproduce asexually through vegetative propagation by forming runners (stolons), bulbs, tubers, corms, suckers (root sprouts), and plantlets. Vascular plants such as pteridophytes, gymnosperms (seed-producing plants), angiosperms (flowering plants), clubmosses, horsetails, and ferns reproduce by spore formation. Other examples include hazel trees, blueberry plants, the Pando trees, the American sweetgum, Myrica, the Kentucky coffee tree, etc.
5. Plants (Artificial Cloning)
The plants grown in nurseries, flower markets, and grocery stores are all artificial cloning examples in real life. Depending on the plant species, there are several methods used for artificial cloning, including cutting, grafting, layering, budding, division, and tissue culture techniques.
Animals that lack sex chromosomes have no other option to procreate other than asexual reproduction. Sharks, Starfish, Crayfish, Planarians, Bees, water fleas, wasps, aphids, and ants reproduce by parthenogenesis. This is an example of natural cloning.
The first fish clone was created by Tong Dizhou in 1963. It was an Asian carp created after the insertion of a male Asian carp’s DNA into the egg of a female Asian carp. Using the same method, he later cloned a European crucian carp as well. This is an example of artificial cloning. This is an example of artificial cloning.
Probably the most popular name associated with successful animal cloning is Dolly, the first cloned mammal. Dolly was cloned by a team of Scottish scientists at the Roslin Institute in 1996. She was cloned from the somatic cell of a 6-year-old sheep. It was however not an easy task, since the team finally achieved the result after 276 attempts. Dolly spent her entire life at the Roslin Institute and gave birth to her progenies. She died at the age of 6. This is an example of artificial cloning.
Mice are one of the most preferred test subjects in science, so their cloning attempt does not come as a surprise. Cumulina was cloned in Hawaii in 1997. She was the first successfully cloned mouse. She died at the age of 2 years and 7 months. This is an example of artificial cloning.
Noto and Kaga were the cows cloned by Japanese scientists in 1998. They have been used as original cloning subjects in the following years and are credited to have paved the way for the next generation of genetically engineered cows. Kaga died on 10 October 2019, after her twin sister Nato died a year prior. This is an example of artificial cloning.
Goats are beneficial commercial livestock farmed for their meat, milk, skin, and fibre. In 1998, a goat named Mira and her sisters were successfully cloned in the US. Mira and her sisters served a great purpose as predecessors of farm animal cloning for subsequent pharmaceutical innovations. This is an example of artificial cloning.
Five piglets named Millie, Christa, Carrel, Dotcom, and Alexis were cloned from adult pig cells in 2000 in the US. Their creation was meant for the possibility of using pig cells and organs for human transplantation. This is an example of artificial cloning.
13. Rhesus Monkey
In the same year, a team of scientists from the Oregon Regional Primate Research Centre created the first Rhesus Monkey clone named Tetra. It was the first of its line of test subjects created to learn about human diseases such as diabetes. This is an example of artificial cloning.
Researchers at Texas A&M University cloned a cat, nicknamed Carbon Copy (CC) on 22 December 2001 via surrogacy. She had different fur patterns than her surrogate mother but was genetically identical to her. The difference in fur patterns might be cited to developmental factors. This is an example of artificial cloning.
Cloning was intended for many purposes. One of them was fulfilled with the successful cloning of a Mouflon named Ombretta. Mouflons were an endangered species until saved with the successful cloning of Ombretta in 2001. This proved that cloning has greater potential for saving the species besides research and commercial purposes. This is an example of artificial cloning.
Ralph, the world’s first cloned rat was created by a team of researchers at the National Institute for Agricultural Research in France in 2002. It was the firstborn among its two siblings. The results were hard to achieve due to the instability of rat embryos. Ralph was cloned for medical research including testing the impact of genetics on the development of diseases. This is an example of artificial cloning.
A white-tailed deer named Dewey was cloned by researchers at Texas A&M in 2003. Dewey was cloned by incorporating the skin cells from a dead white-tailed buck into its surrogate mother named Sweet Pea. Dewey is alive and well in College Station, TX. This is an example of artificial cloning.
In 2003, an Italian research team cloned a female horse named Prometea from a donor horse which was also its biological mother. Earlier, it was believed to avoid doing so due to the speculated health problems in the clone. However, Prometea was born healthy in a natural delivery. This is an example of artificial cloning.
The first cloned mule named Idaho Gem (born on 4 May 2003), and its successor mules named Utah Pioneer (born on June 9), and Idaho Star (born on July 27) are racing mules. Idaho Gem was created with the joint collaboration of Dr Gordon Woods, Dr Dirk Vanderwall, and Dr Ken White. The latter mules were successful results of Project Idaho, financed by the president of the American Mule Racing Association, Don Jacklin, who reportedly still owns Idaho Gem. This is an example of artificial cloning.
In 2004, Ferrets named Libby and Lilly were cloned by somatic cell nuclear transfer. These genetically defined ferrets were created to study transmissible and inherited human lung diseases as these were considered the ideal ones for the same. This is an example of artificial cloning.
A dog named Snuppy was cloned by researchers in South Korea in 2005, using adult skin cells from an adult Afghan hound. Snuppy was a solo success after the attempt of implanting 123 surrogate dogs with 1,095 dog embryos, resulting in just two births. The other puppy died shortly after, leaving Snupy as the lone survivor. Snuppy died in 2015 at the age of 10. This is an example of artificial cloning.
In 2019, as another example of dog cloning, American actor Barbra Streisand stated that she cloned three dogs from her previous dog named Samantha.
South Korean researchers made another accomplishment with the successful cloning of two gray wolf pups named Snuwolf and Snuwolffy in 2005. Both were born in October, 8 days apart. Dogs were used as surrogates since Gray wolves are an endangered species and thus it was difficult to obtain its eggs for cloning. In 2009, Snuwolf died due to natural causes, while Snuwolffy is alive and well at the zoo in Seoul Grand Park. This is an example of artificial cloning.
Debate over Cloning
The ethical concern with artificial cloning is a sensitive issue that needs to be addressed properly. However, cloning is a fundamental biological process of procreation, and without it, species on Earth will go extinct over time. Whether natural or artificial, cloning serves the purpose of preservation of life.