Sports is a really bad example for the point you are Tryingnto make. Region, altitude, humidity, weather, culture they all play a role in what sport a region dominates. You Dont see a lot of black people that dominate in winter olympics, could it be because they share no cultural interest because they may have not been in touch with such interests growing up. Believe me, genes have a role, but it is not a significant factor. This is a multivariable problem, much like the so called pay gap. Once you account for all the variables the difference is insignificant.