Well, since the left gene is a recessive trait, it should not be more popular thing, im right handed by the way, i do everything right handed, and im a homozygous for it ( It means i dont carry the recesive left handed trait ), but most people in the world are probably hetrozygous for it (You carry both Reccesive and dominant genes) But the right handed gene is the dominant one, so the only way you can be naturaly left handed, is when you have only the both recessive traits...
Im sorry, i learned about all this in science today, it actually was usefull, hooray...