My opinion is that you can't stop it because it is a byproduct of other things that are desirable (the difference between CRISPR'ing pigs to be less fatty and CRISPR'ing humans to be less fatty will become increasingly less of a technical difference, and more of an ethical one), and most of the scariest parts of these changes are only scary when they're concentrated and controlled.
The best solution to this is to democratize it by making it less expensive.
One worry is that discrimination would come naturally with the next generation. A majority would never vote itself as second class citizens - but if traditional people weren't the majority then it's a possibility.
The best solution to this is to democratize it by making it less expensive.