My roommates friend brought over her momma rat for us to see and show us her babies. (why she wants to breed for feeders when she only has one ball python is beyond me) Anyway, out of the litter, there were several berkshires and three interesting ones. They are white with these grayish tan markings just before their tail. No other markings on the body, just there right before their bums. Its a very faded marking but very pretty. I was wondering if anyone knew what this kind of marking is called and are there any genetic problems linked to it? I can't get a picture until they are weaned (they are just opening their eyes). I told her I wanted one as soon as they are old enough to be weaned.