In 1997, after more than 260 failed attempts, scientists at Scotland's Roslin Institute successfully "created" a sheep named "Dolly." The achievement prompted much discussion over the possibility of cloning humans (particularly for the purpose of organ transplants) and the ethical implications of doing so, including Kazuo Ishiguro's acclaimed novel "Never Let Me Go," made into a film in 2010.
Cloning to Treat Disease
To date, researchers have yet to clone a human being. They have, however, cloned human embryos for the purpose of harvesting stem cells. This was first done in November, 2001. Stem cells are important for researchers because they can be used for replicating any other cell within the human body. Many see stem cell production as a step toward treatment for diseases such as cancer. Healthy, artificially produced cells and organs would replace those damaged by disease. This type of cloning is called therapeutic cloning.
Cloning Human Organs
Unlike the dark picture painted in certain popular films, cloning human organs for transplants would not involve cloning entire human beings and then "harvesting" their body parts. Instead, scientists would extract DNA from the person in need of a transplant, then insert it into a young egg, at which point it would produce stem cells that could eventually be used to generate tissue or an entire replacement organ. At present, however, there are serious limitations on the technology used for replicating stem cells--not the least of which is a 90 per cent failure rate. The process is also extremely expensive.
The ethical issues facing therapeutic cloning are largely related to the use of embryonic stem cells. Many people regard these cells as the building blocks for a human life and consider attempts to harvest material from them as murder. The ethics of stem cell use (and cloning) were subject to much public debate during the recent presidency of George W. Bush.