A wing is simply a modified foreleg. There is no "wing gene."
Yeah, I was being a bit tongue and cheek with it. The point I was trying to make is; in the million years or so for the foreleg to make its journey to flight, the appendage would be particularly unhelpful to flying or running. I'd think with a million year competitive disadvantage any species would be hard pressed to survive long enough to take wing (or most any other major transition).