Asian people are known for being very studious. Most Japanese children, for example, don't only attend regular school like us, but also cram school after the regular school hours are over. Some start with cram school already when they are only eight years old.
The type of school you go to and the name of the school is very important to Japanese students (for example, most government officials and ministers have a degree of Todai - Tokyo university. It doesn't matter what you study, as long as it's from a precious university) and they all strive to be the best.
So most of their intelligence comes from studying long and hard, not from having it natural.
I don't know what it is like for the rest of Asia, though I do know that Chinese children have to study a lot as well.