There are many reasons designer genes are wrong, and many unforeseen consequences. The majority of scientists think that customizing genes is wrong.
You can’t just make “better people” using engineering (theoretically). In World War II, Adolf Hitler tried to make his own “Master Race”. He wanted to give everyone blonde hair and blue eyes by means of genetic engineering (O.I). Scientists in China attempted to do the same thing (O.I). Scientist have also found a way to insert genes to nullify pain (Doc.2). However, this is not necessarily a good thing. Pain exists to notify your brain when your body is in trouble, without this people wouldn’t