The extra-toes cat isn't a breed. It's a name for any cat born with polydactyly, a harmless genetic variation that adds toes to one or more paws. The trait is dominant, so a cat with one affected parent may have it, and it turns up in domestic shorthairs and longhairs as often as anywhere. Nicknames like Hemingway cat, mitten cat and thumb cat all describe the same wide, mitten-shaped paw.
Because the trait says nothing about coat, size or personality, a cat's age and coat matter more than the toes. Most weigh 6 to 15 pounds and live 12 to 18 years, so adopting one is a long commitment. Shedding is moderate, and brushing needs depend on coat length. The main extra chore is trimming claws, since extra nails can curl into the paw pads.