American Shorthair vs Somali

The 'all-American working cat' story implies a hardy, mixed-heritage constitution, but this is a closed pedigree bred like any other purebred, and Cornell's feline health center lists American Shorthair among the breeds with an elevated rate of hypertrophic cardiomyopathy — the same silent heart disease people specifically worry about in Maine Coons.

Because it's a longhaired Abyssinian, the Somali inherited the Abyssinian's unusually high rate of pyruvate kinase deficiency — in tested Somali populations the mutant gene has been found in 10% to 28% of cats sampled across different countries — a disease that causes lifelong, incurable anemia in cats that inherit it from both parents.