I would agree with the "no breeds, just varieties". Not all hoodies are Long-Evans, it's just a coat pattern, you can get hooded rats in hairless, rex or just plain standard type in any colour.

Long-Evans is one strain of lab rats that all have hoods. Y'know hoodies were originally called "Japanese" (and still are in some languages)? Not a clue why, I can't find any evidence of them having any origin in Japan.
I don't think there's enough difference between rats to call them breeds, most of the striking differences (dumbo, hairless etc) are only caused by one little recessive gene. My little black dumbo self had a dumbo hairless brother, and I've seen plenty of mixed dumbo/top ear litters. It depends how you use the word breed.
Also: I have a theory that the differences people claim about dumbos (bigger, soppier) may have once been true, but would have only applied to the original stock. The first breeders of dumbos probably selected rats for size and docile temperament, but this isn't relevant now that the gene is much more common in rats everywhere. Again, just a theory that I'd really like to do research on.