To clone or not to clone, that is the question. Or at least, that’s the question addressed in Nicholas Agar’s clear and well written book.
He starts from the science of cloning. Pretty well all of us have opinions about the whole business without having a clue about what’s actually involved. The science isn’t as straightforward as you might think (so perhaps its no surprise it’s so difficult). For example, it’s not widely understood that the famous cloned sheep Dolly is actually less of a clone than a perfectly normal identical twin. The identical twins share the same DNA (apart from any mutations), but Dolly’s cloned material was her nuclear DNA – the DNA that normally comes half from each parent. The other, less frequently mentioned DNA, mitochondrial DNA came not from the sheep she was cloned from but from the donor of the egg. This DNA, which has proved valuable in the past for tracing the maternal line as it normally comes only from the mother, may not have much to do with the development of the embryo (and hence Dolly was to all intents and purposes a clone), but it does mean there is a distinction here.
With the science firmly established in some very readable text, Agar goes on to the ethics and the potential applications of cloning. Here, sometimes his line is a little less clear. While he picks up the point that the extreme supporters of abortion are also happy to kill newborn babies for convenience, because at this stage they are not yet people, and so argues that it’s possible to justify letting a cloned human be produced as most problems can be solved by destruction on detection, he doesn’t really follow through the reverse argument that most people are horrified with the concept of killing newborn babies for convenience, and so are unlikely to accept arguments derived from this premise.
What Agar makes clear is why cloning is difficult – a lot can go wrong in trying to switch back on all the genes that have been deactivated in an adult human. He also successfully destroys the idea of cloning as a means of living forever, makes therapeutic cloning seem eminently reasonable, and makes it clear that cloning as means of supplying babies for the infertile isn’t wrong in principle (though the current state of the technology makes it anything but desirable).
All in all a valuable addition to informed debate.