Hmm. I blame inbreeding. Seeing as two members claim having snakes with this upside-down disorder, both being albino checkereds, I'd see it as a result of the breed. I'm pretty sure that to get an albino checkered garter snake, like many of the corn snake varieties, there was inbreeding. Probably heavy inbreeding, seeing as not many people are into garter as compared to ball puthons or corn snakes, and a pair of albinos would have been hard to come by.