The AMFRA has information about odd eyes and megacolon as well. Apparently, it's not the odd eye trait itself that causes it, but rather the tendency of high white rats and mice to develop this problem.

I highlighted a few articles for you:
http://www.afrma.org/c-c_oddeyeetc.htm

http://www.afrma.org/megacecum.htm

Gale