We are often told by the PC police that the environment someone is raised in is far more important than their hereditary traits. I am willing to believe that, but only with evidence. I will use Colin Kaepernick as my example.
"Kaperneick sucks, why him?" Sure he sucks, if you compare him to the very best in the world. He is a better quarterback than 99.9 % of the general population.
Both of Kaepernick's parents (biological, that is) were very athletic. His adopted family was not. Both his white mother and black father (biological) were athletic. That's also why I wanted to use him as an example: I don't want to turn this into a white people vs black people thing. You have a biracial man where both parents were just as athletic as each other, the only difference is one is white and the other is black.
Steve Jobs biological parents were very intelligent. His adopted family, meh. He also has a biological sister who he never even met until well into his adult years, who is also very successful. Not as much as him of course, but you get the picture.
I think this paints an overly simplistic view of how a person's genes actually manifest themselves.
A genetic capacity for excellence, athleticism or intelligence or whatever, does not automatically exhibit itself. Kaepernick's biological parents not only had the genetic capacity for athleticism, but acted upon it, as did Kaepernick himself. If none of them had, we wouldn't recognise this capacity because it was never realised. Perhaps his adoptive parents had a comparable or greater capacity for athleticism, but never acted to realise it. Indeed, their could be whole dynasties of natural Olympians, but if all of them lead inactive lifestyles and have poor diets, or if they were to live in a time and a place with few opportunities to practice athletics, or even simply the kinds of athletics they were have that natural capacity for- the difference between an Olympic runner and an Olympic power-lifter ins't just between career paths- we'd never know. If we assume that a genetic capacity for excellence
always exhibits itself, and that a failure to exhibit excellence
always indicates a lack of that capacity, we're liable to start finding all sorts of patterns where none exist.
Further, genetics is complicated, and natural capacities don't sit on a sliding scale from "exhibited" to "not-exhibited": a person has dozens, hundreds of natural inclinations, and they interact in complex ways. A person might have a natural capacity for most aspects of athleticism, but some other physical qualities that limit their development, like a digestive disorder or a weak cardiovascular system. A person might have a natural capacity for athleticism, but also an natural tendency towards depression or anorexia, or a natural aversion to conflict and competition. Genes aren't materia and the body isn't the Buster Sword: they can't be treated like isolated potentials and the body like a neutral vehicle, rather, the whole thing is a complex and messy interaction of potentials, limits, inclinations, aversions, and just plain biological noise that only makes sense when you put it all into a living human being who is effectively inseparable from his physical and historical context.
Put briefly, there's no Win At Football gene, because that's not how nature works, so trying to hunt down the Win At Football genes in the population and draw familial connections between them is just going to leave you with a mess of lines pointing nowhere.