The Dearly Beloved Stephen Pinker (the Fifth Horseman?) has an excellent article on the Morality Instinct (good material to smite the 'God made right and wrong' crowd, btw).

In passing, he mentioned the 'ick' response, and how badly it's abused:

In "The Wisdom of Repugnance," Leon Kass, former chair of the President's Council on Bioethics, argued that we should disregard reason when it comes to cloning and other biomedical technologies and go with our gut: "We are repelled by the prospect of cloning human beings . . . because we intuit and feel, immediately and without argument, the violation of things that we rightfully hold dear. . . . In this age in which everything is held to be permissible so long as it is freely done . . . repugnance may be the only voice left that speaks up to defend the central core of our humanity. Shallow are the souls that have forgotten how to shudder."

Pinker points out that turning off your brain and going with your shudders would have ruled out a range of currently acceptable items:

'There are, of course, good reasons to regulate human cloning, but the shudder test is not one of them. People have shuddered at all kinds of morally irrelevant violations of purity in their culture: touching an untouchable, drinking from the same water fountain as a Negro, allowing Jewish blood to mix with Aryan blood, tolerating sodomy between consenting men. And if our ancestors' repugnance had carried the day, we never would have had autopsies, vaccinations, blood transfusions, artificial insemination, organ transplants and in vitro fertilization, all of which were denounced as immoral when they were new.'

The full article - highly recommended - is at
http://www.nytimes.com/2008/01/13/magazine/13Psychology-t.html?_r=1&scp=1&sq=&st=nyt&oref=slogin

CD