I think that there are two fallacies at the bottom of a lot of the thinking here.
From Wikipedia:
”Appeal to nature is a commonly seen fallacy of relevance consisting of a claim that something is good or right because it is natural, or that something is bad or wrong because it is unnatural. In this type of fallacy nature is often implied as an ideal or desired state of being, a state of how things were, should be, or are: in this sense an appeal to nature may resemble an appeal to tradition.
and
“The anthropomorphic fallacy is the treatment of inanimate objects as if they had human feelings, thoughts, or sensations.”
A lot of people seem to be opposing the idea because it isn’t “natural”. It’s important to understand that nature is not looking out for us, and does not have our best interests in mind, nature “intends” nothing because nature is not a person.
@ shilolo – I think you’re being influenced by the anthropomorphic fallacy, but in a more subtle way. Some apparently negative genes might have a “silver lining”, but not every disease is a blessing in disguise. Occasionally a gene will remain in the pool because it has some hidden benefit, but it is safe to say that Harlequin Icthyosis, for example, has none. The hidden benefits of some genes are not part of a grand plan orchestrated by nature, as I’m sure you know, and though I agree that we may not always be able to predict the outcomes of our actions, trusting our future to a blind, uncaring, and utterly amoral system seems far more dangerous to me than the alternative.