Well, I don't think there is anything wrong with genetically engineering someone to prevent a disease, but to take it as far as to make them act, think, react, or perform in a certain way is ethically immoral.

Now, the way I understand it, Gene Therapy is used to heal, prevent, or what have you, any defects that deal with diseases. While Eugenics deals with altering someone chromosomes so that they will be more intelligent, or more athletic, etc. To me, they are two completely different purposes in science. One is healing a mutated or abnormal gene, and the other is basically fucking with human evolution.