Why have you NOT taken him to the vet? I'm sorry but this has me steamed! How sad for this poor rat. You are just letting him suffer! He's probably sneezing stuff out because you have avoided getting him the proper vet care. Just because he is inbred (it's not that bad with rats if you would listen and do research. Ask many of the top breeders. A lot of the traits we have are set through inbreeding/linebreeding) does not mean this poor guy has to have his tombstone chizzled already. You are very irresponsible. Just so you know it's very common for male rats to have an orangish color to their skin. It's caused by the protein the skin creates, and males just happen to have more than females. If they have too much protein in their diet it gets worse. It can also be caused from having a dirty cage. Also, if I was that rat and had such a horrible life living in that house I'd probably be a bit aggressive too. Just a thought. Maybe you should take care of your animals.