Just to take one example of a genetic feature in the wild, there is a gene receptor which if you have the right mutation will cause an 25-50% increase in oxygen

Just to take one example of a genetic feature in the wild, there is a gene receptor which if you have the right mutation will cause an 25-50% increase in oxygen carrying capacity of red blood cells. Some people call it a naturally occurring blood doping. The definition of fairness is difficult when dealing with even single genetic features.