That does get at my point though. While there obviously isn't a single "Shaq gene" or "Lebron gene", I also don't think we could reliably identify even a very large suite of genes that could be tweaked to result in increased "Shaq-ness" or "Lebron-ness". And beyond that, we certainly aren't anywhere close to identifying a "likes basketball" gene.
While I agree with the difficulty to impossibility of finding those specific genes, a whole genotype 'nearest neighbor' or other classification criteria is very interesting:
Considering that both the 'Shaq' phenotype and genotype are known, it wouldn't be too difficult[0] to rank 10,000 embryos per couple in terms of closeness to the 'Shaq' genotype. Then cross reference and weight the 'Shaq-likeness' ranking with the 'Jordan-likeness' ranking and the 'Gretsky-likeness' ranking. To me anyway, that seems like a recipe[1] for, statistically, dramatically improving one's offspring's odds at being a professional basketball player.
[0]Mathematically, anyway
[1]As a counter point, I'd expect to see this sort of thing take off in horse racing if it was productive. Big money and looser ethics.