Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissue. It does not refer to the natural conception and delivery of identical twins.
The possibility of human cloning has raised controversies. These ethical concerns have prompted several nations to pass laws regarding human cloning and its legality.
Two commonly discussed types of theoretical human cloning are: therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of July 2016. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and, more recently, pluripotent stem cell induction. Reproductive cloning would involve making an entire cloned human, instead of just specific cells or tissues.
Main article: Ethics of cloning
In bioethics, the ethics of cloning refers to a variety of ethical positions regarding the practice and possibilities of cloning, especially human cloning. While many of these views are religious in origin, the questions raised by cloning are faced by secular perspectives as well. Human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.
Advocates support the development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants, to avoid the need for immunosuppressive drugs, and to stave off the effects of aging. Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to the technology.
Opposition to therapeutic cloning mainly centers around the status of embryonic stem cells, which has connections with the abortion debate.
Some opponents of reproductive cloning have concerns that technology is not yet developed enough to be safe – for example, the position of the American Association for the Advancement of Science as of 2014, while others emphasize that reproductive cloning could be prone to abuse (leading to the generation of humans whose organs and tissues would be harvested), and have concerns about how cloned individuals could integrate with families and with society at large.
Religious groups are divided, with some opposing the technology as usurping God’s (in monotheistic traditions) place and, to the extent embryos are used, destroying a human life; others support therapeutic cloning’s potential life-saving benefits.