Human Cloning Controversial Research Essay
Uploaded by cracky on May 10, 2005
Human Cloning
The possibility of human cloning was raised when Scottish scientists, led by Dr. Ian Wilmut at the Roslin Institute, created the much-celebrated sheep "Dolly". Being the first mammal ever cloned this aroused worldwide interest and concern because of its scientific and ethical implications. The feat, cited by “Science Magazine” as the “breakthrough of 1997”, also generated uncertainty over the meaning of "cloning" -- an umbrella term traditionally used by scientists to describe different processes for duplicating biological material. Since this creation, mice, goats, cows and pigs have been successfully cloned around the world. This has made human cloning a real possibility.
Cloning is the production of one or more individual plants or animals that are genetically identical to another plant or animal. It is different from natural fertilisation which is "sexual" reproduction that occurs when a sperm fertilises an egg. In normal fertilisation the developing embryo (and person) has the genetic makeup or DNA of both parents 23 chromosomes from the female and 23 from the male. The embryo is the unique human organism with a novel genetic makeup having the full potential to develop to adulthood. Current definitions define "embryo" as follows: “the term `human embryo or embryos’ includes any organism that is derived by fertilisation, parthenogenesis, cloning, or any other means from one or more human gametes or human diploid cells.”
Figure 1: Comparing cloned embryo’s with fertilised embryo’s
Source: Available from URL: http://www.house.gov/weldon/issues/clone_basics.htm#cloning
(Accessed Sunday 15th August 2004)
When the media report on cloning in the news, they are usually talking about only one type called reproductive cloning. There are different types of cloning however, and cloning technologies can be used for other purposes besides producing the genetic twin of another organism. A basic understanding of the different types of cloning is the key to taking an informed stance on current public policy issues and making the best possible personal decisions.
The three main types of cloning are:
1. Embryo cloning
2. Reproductive cloning
3. Therapeutic cloning
Embryo cloning
Embryo cloning might be more accurately called "artificial twinning", because it simulates the mechanism by which twins naturally develop. It involves removing one or more cells from an embryo and encouraging the cell to develop into a separate embryo with the same DNA as the original. It has been successfully carried out for years on many species of animals. Some very limited...