to be a smart ass every locus has multiple alleles, normally 2. My question would be, what discussion were you having where the above had any relevance? (I'm honestly interested) There's plenty that go into the final phenotype of our animals, don't forget epigenetics which opens a big can of worms imo. In theory you could have a pinstripe that looks normal because the expression was turned all the way down. but there hasn't been a reported case of anything resembling it, so why talk about it.