About Different Types of Cloning
One of the most controversial subjects in the world of medical research today is cloning. Researchers contend that cloning can save lives, while others wonder just where do you draw the line and what effect would cloning have to our world if the knowledge ends up in the wrong hands.
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Identification
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There are three types of cloning:
* DNA Cloning--DNA cloning is the oldest form of cloning. DNA cloning began in the 1970s and is a common practice today in molecular biology labs. DNA cloning involves isolating a specific fragment of DNA and inserting it into a rapidly growing host, such as bacteria. The host then replicates the DNA fragment, resulting in the production of billions of copies of the DNA fragment in a short period of time. DNA cloning has been used to create medications such as insulin, human growth hormone and vaccinations for illnesses such as Hepatitis B.
* Reproductive Cloning--In simple terms, reproductive cloning occurs when scientists extract a cell from one animal, remove the nucleus from that cell, and insert a cell from another animal to give the first cell the DNA characteristics of the donor animal. Cell division is then manipulated by using chemicals or an electrical current. Once cell division begins, the cell is then placed into the womb of a surrogate animal. The surrogate animal hosts the cell as it grows and takes on the characteristics of the animal being cloned, and the cloned animal is delivered in a normal delivery. (The Click and Clone link below shows you exactly how this works.)
* Therapeutic Cloning--This type of cloning is also known as embryo cloning and works similar to reproductive cloning. Therapeutic cloning is used to product human embryos that can be used to study human development and to learn more about treating diseases.
Misconceptions
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Along with facts and scientific evidence, cloning is also surrounded by myths:
* Clones are not carbon copies--While a clone will have the same genetic makeup as the model, the clone grows from birth and may develop different characteristics depending on the environment in which the clone grows and the experiences the clone has. The clone may look identical, but the environmental differences will cause the clone to "become its own person."
* You cannot create instant clones--A clone is created using reproduction, just as you were created. That means that the clone is born as a baby and grows to maturity. So, if you like the idea of having a clone to do your chores or fill in for you when you don't want to go somewhere, it just won't happen that way.
* An army of clones--Science fiction would have us believe that an army of robotic clones can be created overnight. As stated above, cloning uses reproduction. This means that it would take years to develop an army using cloning, and environmental differences would make each clone an individual, with his own thought patterns and behaviors.
Risk Factors
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While there has been much success using DNA cloning to develop cures and vaccines for diseases and illnesses, there are many risks involved in reproductive cloning. There have been many animals cloned successfully--sheep, mice, pigs, cows and goats. However, most of the cloned animals suffered from poor health and short lifespans. For instance, Dolly, the famed sheep clone, only lived six years, half the life expectancy of a sheep. Studies have also shown that these animals have a lower immune function and an often higher risk for infections and other illnesses and diseases.
Benefits
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Even with the risks associated with reproductive cloning, there have been benefits to using DNA cloning. DNA cloning has been used to produce insulin for diabetics, tissue plasminogen activator for dissolving blood clots, a vaccination for Hepatitis B, and many other vaccinations and medicines to help control or cure illnesses and diseases. Therapeutic cloning is the most controversial type of cloning, but some scientists hope that some day, they will be able to use this type of cloning to create donor organs and be able to gain an insight into genetic diseases.
Evolution
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The idea of cloning has been around since the 1950s, and successful DNA cloning has been practiced since the '70s. Cloning will remain a controversial topic as long as people "retain" the image of developing cloned armies built to destroy the world and consider therapeutic cloning as "playing God." Science research is far from breaking the realm of developing healthy human clones. The scientific world has years and years of work and development ahead of them. New breakthroughs in the three types of cloning are providing us with medicines and vaccines to manage, prevent and sometimes even cure diseases and illnesses that were a mystery 100 years ago.
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