Manx vs Japanese Bobtail vs American Bobtail: Which Tailless Cat Is It?

Three breeds, one missing tail, and a genetics story most comparison pages get wrong. TICA's own "Similar Breeds" field for the Manx lists the Japanese Bobtail, Kurilian Bobtail, American Bobtail and Pixiebob, which is independent confirmation that this grouping is the real question. Here is how to tell them apart by eye, and the one genetic fact that genuinely separates their health files.

The genetics, corrected

Start with the correction, because even careful sources fumble it: BOTH the Manx's and the Japanese Bobtail's short-tail traits are DOMINANT. (Our own research brief originally assumed one was recessive; reading the papers overturned it, and CFA's own Japanese Bobtail page independently confirms the dominant inheritance.) What genuinely differs is what happens with TWO copies. In the Manx, the T-gene (Brachyury) mutation is homozygous-lethal: no cat has ever been found carrying two mutant copies and surviving to term (Buckingham et al. 2013). In the Japanese Bobtail, the HES7 mutation is routinely tolerated in double dose: in the identifying study (Xu et al. 2016), every one of the twelve purebred Japanese Bobtails tested was homozygous, healthy, and short-tailed. Same visible outcome, opposite genetic risk profile, and it is why Manx Syndrome has no Japanese Bobtail equivalent.

One more published error corrected while we are here: a widely-read consumer site states the American Bobtail "does not share the Manx tailless gene." Buckingham et al.'s own results say otherwise: a shared mutant T allele (c.998delT) was found in both breeds. What no source states is an American Bobtail homozygous-lethality rate, so we do not state one either: the shared allele is the finding, not a transplanted risk figure.

Telling them apart by eye

The Manx: no tail at all or a rump dimple in the show classes (four classes exist, rumpy to longy), a round, cobby body, a rabbit-like hopping gait in some cats, and hind legs longer than the front. The Japanese Bobtail: a short POMPOM tail, kinked and curved, always present, on a slender, refined Asian body type with high cheekbones. The American Bobtail: a short but flexible straight-ish tail, one-third to one-half normal length, on a big, athletic, wild-looking frame. Rump with nothing: think Manx. Pompom: Japanese. Short expressive brush on a linebacker: American.

The Cymric row

The longhaired Manx, called the Cymric in most registries, carries the same T-gene mechanics under a silky semi-long coat: its own page covers the naming maze. For identification purposes it reads as a fluffy Manx, never as a Bobtail.

Which is right for you

If you love the look but want the simplest health file, the Japanese Bobtail's double-dose-tolerated genetics make it the structurally simpler bet; neither Bobtail has a full profile on this site yet, so we say that plainly rather than pretending. If it is the Manx, buy informed: tail classes, breeding-program questions and the syndrome file are all one click away, and an informed Manx buyer gets a wonderful, storied, round cat.