People have been combining the differnt genus' of Pituophis, Lampropeltis and Elaphe (Pantherophis) for decades and the offspring are quite fertile. I'm personally against hybrids. Sure there are some interesting combinations but I've been burned before. Many years ago I bought some 'interesting' looking pine snakes which ended up being hybrids. The next generation was all over the place looks wise, if I hadn't hatched them myself I couldn't have even guessed that they were related.