@Fa5t3r - That argument works on the assumption that humans aren't capable of choosing a better path. That we should throw away any technological advantage that might be misused. If we did that, we would have to throw away all of our technology.
All of these techniques can be used to prevent tragedy and have already done so. They can prevent babies being conceived with debilitating conditions, and farmers from losing all their crops to disease and drought. I don't think we should turn away from these things just because they might be misused.