Get rid of the high white rat and it possibly won't happen anymore? She likely carries hairless and when bred to the mock hairless male, the babies inherited the gene

High whites are not safe options for breeders as they may carry the genes for megacolon and other problems. You can end up with entire litters of suffering and dying pups who slowly starve to death because their colon doesn't work properly(no nerve signals). Can't use them as feeders either as they are not healthy and haven't been able to properly digest any nutrients.