Racism makes people feel sorry for being born a certain way, of having a particular skin colour. Racism has no scientific explanation, and the racist people are entirely ignorant about the feelings of other human beings.
No one can choose to be black, white, dark, fair, or anything in particular. God has made us, and there is nothing that should make us feel guilty for that. It is ridiculous and inhumane to make fun of people due to their cultural background or colour of skin.