This is an interesting question, because the different ethical situations presented in that movie are hypothetical, based on one possible scenario that might exist in our world if genetic engineering is taken into the realm of fertility and parenthood.
In this movie, discrimination exists not based on skin color, socio-economic class, culture or religion, bur rather on whether or not you were engineered to be perfect. The ethical issue presented deals with the question of whether it is right to discriminate based on that; the movie itself seems to point out that not, it isn't. Take the main character, for example. He is a "natural" child, and yet his character--his determination, drive, hard-working mentality, goals, ambition--is much stronger, likable and better than that of the genetically altered person that he borrows DNA from. His donor DNA person is selfish, lazy, embittered and prideful.
The movie also asserts that genetic engineering does not gurantee happiness or success; it shows that the true thing that matters is a person's determination. In the end, it is the man who was most determined--not most skilled--that ends up being happy and achieving his dreams.
I believe that the ethical scenarios presented are a pretty realistic projection into the world that was created. It seems that people are always searching for ways to discriminate, divide and hold pride in their hearts; genetic engineering was just a different channel for those tendencies to be funnelled through. I hope that helps; good luck!
What are the:
1) Possible positive advantages of Eugenic control of the population.
2) Possible negatives/disadvantages of Eugenic control of the population.