When I read the fact in this news saying that "0.1% of European and American have a mutated gene which confers them the resistance to AIDs virus", one question had come up to my mind.
 
Could this be the phenomenon which has been happening throughout the course of human natural history repeatedly?

I meant that, at times along the journey of human beings through their history, there would be many different kinds of life-threatening viruses and only few percents of humans were be able to escape from them and survive. (We're looking back to the very ancient period (millions of years ago) which no one had ever heard of viruses before and, thus, had known nothing about how to protect themselves.) These small percents of humans must have (an) advantageous gene(s).

If this group of human also had other novel genes that introduce them new or better characteristics and abilities over ancestors, through time they would suit best to the environment niche where they lived. (The present-day humans are the result of this very long long process. We are pretty robust, nevertheless new life-threatening viruses are always emerging from time to time to defeat us.)

Life-threatening viruses have been one of the important determinants in natural selection, until humans find how to cure their infections.

 

This illustration shows particles of HIV-1 through an Atomic Force Microscope (with permission from Professor A. McPherson).