American Shorthair — questions to ask before paying a deposit
A responsible breeder will have these readily available. Deflection is a red flag.
Hypertrophic cardiomyopathy (HCM)can shorten life or cause chronic pain
A thickening of the heart muscle that can lead to heart failure or sudden death. It has long been reported as inherited in a family of American Shorthairs, and the breed is regularly named alongside Maine Coon and Ragdoll as predisposed. Unlike those two breeds, no breed-validated DNA marker exists for American Shorthair, so genetic testing cannot rule it out.
Ask to see: No breed-validated DNA test exists — ask for a recent echocardiogram, read by a cardiologist, on both parents
Cornell Feline Health Center — Hypertrophic Cardiomyopathy (https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/hypertrophic-cardiomyopathy) · Fujii et al. 2023, PLOS ONE — ALMS1 and MYBPC3 variants in a diverse cohort of cats with HCM in Japan (https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0283433)
Progressive retinal atrophy (PRA rdAc, CEP290) — minor, secondary finding
A 2009 genetic survey found the CEP290 mutation responsible for inherited blindness in Abyssinian and Somali cats also present, at low frequency, in American Shorthairs. This is a minor secondary finding rather than an established clinical problem in the breed, but the same DNA test used in the higher-risk breeds can be run if a line's ancestry is of particular concern.
Ask to see: UC Davis VGL PRA rdAc (CEP290) DNA test result, on both parents (optional; lower priority than in Abyssinian-group breeds)
UC Davis VGL — PRA rdAc (CEP290) test (https://vgl.ucdavis.edu/test/pra-rdac) · Menotti-Raymond et al. 2009, The Veterinary Journal (https://doi.org/10.1016/j.tvjl.2009.08.010)
Protruding sternum
An outward or inward bend in the lower chest bone. CFA notes it is seen mostly in oriental-type breeds but has also been observed, less often, in American Shorthairs. An outward protrusion is typically harmless; an inward one can press on the chest cavity and needs veterinary assessment.
Ask to see: No DNA test exists — ask for a veterinary chest exam noting sternum conformation, on both parents
Cat Fanciers' Association — Genetic Disorders (https://cfa.org/genetic-disorders/)