Well, it depends on what you believe.
People would see it blasfemous(sp?) against God by manipulating his creation into something we perfer.
Then again, what if it helps the person for a better living?
Have you seen the movie "Gattaca"? Its a good movie to watch since it deals with something similar to your question. It involves genetic engineering and its really neat movie to watch.
[I apologize if my answer seems so simple, but I'm just 15

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