I'm exceptionally good at first person shooter games. Does that mean there's a specific gene responsible? I think not.
Though trite, there's some truth in the age old saying "practice makes perfect".
People DEVELOP their skills over time.
Nobody's born with the ability to draw (yea...I bet Botticelli could paint when he was 5), and by the same token, nobody's born with any real tangible skills. Essentially, we're just pieces of clay molded by our experiences over time.
However, I won't discount the fact that say...being muscular might affect one's performance in say...boxing...or that being tall may affect one's performance in say...basketball. In many situations, one's genes may indeed affect one's ability to perform a specific task. However, the ABILITY to box, isn't innate, and neither is the ability to dunk a basketball. If such 'skills' were innate, then people wouldn't need to train.
We could go on in circles forever discussing this nature vs. nurture stuff.