Anyone that refutes genetics as a huge factor in any sport is completely idotic.
Of course Jordan's kids are bad at basketball, that's because Jordan is still making millions off of how good he was at the game, where is the motivation to be good at something when you're already rich because someone else did it?
Look at the Jones Family, Jon Jones is the Light Heavyweight champion in the UFC, his brothers both play in the NFL.
There are also countless twins in collegiate running and Olympic sports.
The Morris brothers in Basketball, the Pouncey twins in Football, the Sedin Twins in Hockey. Family genetics is a huge factor in being succesful on a professional scale.
The biggest problem is, you'll never get world class talent generation after generation to breed together and train their children to do the same to actually see the beenfits.
If Jeter and Bekele had a child it would most likely take after either the mother or the father, the perfect storm of Bekele's Endurance combining with Jeter's raw speed would end creating the next Caster Semenya.
Until the science of Gattica becomes a reality, we're simply going to have to breed our low class collegiates together and hope for the best.