Friday, July 13, 2007

The Clone Wars

I don’t see anything intrinsically wrong with reproductive cloning.

I think it would be handy for all sorts of people who because of disease, accident, sexual orientation, or vocation, are unable to pass on their genetic material in the regular way. It has two problems, but these are problems shared by other assissted reproductive technologies:
(1) Wastage of ‘surplus’ embryos. I know nature does this, but I still think we should strive to keep it to a minimum.
(2) Health problems in the offspring. These are well documented but relatively minor for children put together by in vitro fertilisation. With cloning on the other hand, in the mammals we have looked at so far there are all sorts of peculiar and unexplained health problems. It would be criminal to experiment on human reproductive cloning at the moment because of these problems.

But there is no reason we should not keep on experimenting on our near relatives. Primates seem to be tricky things to clone. By all means let us try to clone chimpanzees. Once we can reliably clone perfectly healthy chimpanzees with a minimum of embryo wastage, why not apply the same technology to ourselves? I see no rational reason not to.

I do see therapeutic cloning as intrinsically wrong.

I think deliberately creating human embryos in order to destroy them is going too far. I don’t lose a great deal of sleep over it, because I was lucky enough to hear a talk in February 2006 by Graham Parker who is on the board of the journal ‘Stem Cell Research’ and works at a research hospital in Michigan. I learned the following things:

(1) The more differentiated a stem cell is when you start messing around with it, the more effective it is. This is why we still need to donate blood, and don’t just culture haemotopoetic stem cells. Inner-cell-mass-derived (aka embryonic) stem cells are less differentiated than somatic (aka adult) stem cells and appear much more likely to turn into invasive cancers when you inject them into mice.

(2) Nobody has a clue how stem cells really work clinically. It does not look like they just move in and turn into the sort of cells that are around them. They do other weird things that nobody understands yet.

(3) The chaps who first discovered inner-cell-mass-derived stem cells never claimed they had clinical uses. They still don’t. They are of fundamental importance in understanding developmental biology, which is important fundamental research and will eventually lead to all sorts of innovations- but they won’t involve injecting people with stem cells. 97+% of this fundamental research could (and should) be done with stem cells of the other mammals that we share so much of our DNA with.

This suggests to me that we are not likely ever to have a situation where therapeutic cloning would be done on an industrial scale and would be a big moral quandary for anyone with a serious illness. And if someone says, ‘I want to experiment on human embryonic stem cells’, the correct response is, ‘go do your experiments on chimpanzee embryonic stem cells’. There is no justification for playing with human embryonic stem cells. Maybe, once you have demonstrated that you can reliably and safely repair damaged chimpanzee brains, or whatever, then we can sit down and have a debate on extending the technology to humans.

No comments: