Science is not ‘stand-alone’. Many scientific discoveries have social and ethical implications and further, some actual experiments or investigations may be regarded as unethical. Against this background we consider cloning. Cloning of plants has been in use in agriculture and horticulture for many hundreds or even thousands of years, initially by methods such as taking cuttings but since the early 1960s also by cell and tissue culture (as in the cauliflower cloning exercise). Some plants clone themselves naturally: the ‘average’ nettle patch is a large clonal colony.
Cloning of animals, especially vertebrate animals, is more difficult. It was John Gurdon’s research group working in the early 1960s that first cloned frogs by the technique of nuclear transfer from an adult cell. This was exciting news because it showed that genes which are switched off during development can be switched on again. However, cloning of mammals is much more difficult. In the late 1980s, mice, sheep and then pigs and cattle were cloned by nuclear transfer from embryo cells but it was not until 1996 that Dolly was born – the first mammal to be cloned by nuclear transfer from an adult cell. This was scientifically very exciting but also sparked off a lot of ethical debate in relation to possible cloning of humans (see below). Since Dolly, several other mammals have been cloned, including rats, mice, pigs, cattle, horses, dogs and cats. Cloning of pet dogs and cats is available to order (at a price!), milk and meat from cloned cattle is in the human food supply chain and a cloned polo pony is currently being ridden in matches in South America. However, cloning of primates has proved very difficult – no attempts at reproductive cloning of any primate have been successful.
When Dolly was shown to the public, many of journalists and commentators wanted to know whether human cloning would be possible. In theory the answer is ‘Yes’ and that raises ethical issues which require careful thought. What actually is morally right and what is morally wrong in this area and how do we decide? What type of ethical framework do we use? In most countries in which relevant laws have been made, reproductive cloning of humans is regarded as morally wrong and is banned. In the UK and several other countries however, it is not illegal to create human embryos by cloning in order to obtain embryonic stem cells, so-called therapeutic cloning. But even that has proved extremely difficult.
But even if it were possible to clone humans, would we be making exact copies of particular people? Only in the genetic sense. Clones are genetic copies but cloning cannot reproduce all the other influences and factors that contribute to who we are. Even identical twins (natural clones) may turn out to be very different from each other, despite their being born from the same womb and growing up in the same home (‘nurture’). Thus, cloning an elite athlete would not guarantee that we would get another elite athlete because we are so much more than our genes.
Although it was published ten years ago, Introduction to Bioethics, Bryant, la Velle and Searle, publ Wiley, is still very relevant – see Chapter 9. A second edition is in preparation and will be published in 2016.
Beyond Human, Bryant, publ by Lion (2013) is also worth reading, especially Chapters 7 and 9. Indeed, at £9.99 it is cheap enough to buy for the LASAR library.
Cloning a Sports Star
Housekeeping Genes by Joseph