Your portfolio would have to be FANTASTIC to make up for the lack of a degree. It's entirely possible, I think, to program without a degree but you have to be really really good. But you should apply anyway without the degree just in case you get lucky or something. The big, well known, or prestigious companies like id software (I think all their positions have some sort of degree as a Desired Skill since id is like the Harvard of gaming) can demand a college degree and get it but small game shops don't have that luxury.