Therapeutic Cloning vs. Reproductive Cloning

In the past few decades, there has been much talk about the place that cloning should have in our society. Recent advances in cloning procedures have sparked great controversy and debate over the entire cloning issue, and many laws have been passed banning cloning for specific purposes. In general, there are two main purposes for cloning: medical therapy and reproduction. Known as therapeutic cloning and reproductive cloning, both of these procedures are being used actively in some countries for research purposes. Although umbilical cord blood stem cells are not currently used for either type of cloning procedure, there is hope that some day they will be.

What is Cloning?
Cloning refers to the process of making a genetic duplicate of something that already exists. We often think of cloning in human or animal terms - for instance, Dolly, the cloned-sheep - however, single cells and genes can also be cloned. There are a variety of different ways to clone an organism and these procedures are governed by different organizations in every country.

Cloning has been a highly controversial subject as of late, but in fact, cloning has been around for many years. Plants have been cloned for decades and the first animal to be cloned was a tadpole in the 1950s. Since that time, a number of animals have been cloned, including sheep, cows and mice.

Types of Cloning
There are two main types of cloning: reproductive cloning and therapeutic cloning. These procedures are governed by different laws because they are used for different purposes.

 

Reproductive Cloning

Reproductive cloning is performed with the express intent of creating another organism. This organism is the exact duplicate of one that already exists or has existed in the past. Cloning of plants, animals, and humans falls into the class of reproductive cloning.

How is Reproductive Cloning Performed?
Reproductive cloning is performed using a technique called Somatic Cell Nuclear Transfer (SCNT). The genetic material from a donor egg is removed, so that you are left with an empty egg. Then, a cell is taken from the organism to be cloned and its nucleus is removed. This nucleus is then transferred into the empty donor egg. Using chemicals or a mild electric shock, the egg is forced to divide, creating an embryo. This embryo is then transferred into the uterus of the host organism.