Cat With No Tail? The Breeds, the Genes, and What a Missing Tail Means

The Manx is the only major breed whose show classes are built around genuine taillessness. Its tail spectrum runs four classes, from the completely tailless rumpy through riser and stumpy to the near-normal longy, and only the tailless end competes. The gene is the T-gene (Brachyury), dominant, and homozygous-lethal. Every living Manx carries one copy, never two.

That is why tailed kittens appear in Manx litters, and why responsible breeding pairs tailless with tailed. The same gene at its tailless extreme is why the breed carries a real, documented health file (Manx syndrome, a spinal condition), which our Manx profile covers with each registry's own wording rather than a summary. The longhaired version is judged as the Cymric in some registries, and as a Manx division in others.

Four established breeds wear a short tail that is never quite absent, and they split cleanly into two genetic camps. In the T-gene camp with the Manx: the American Bobtail (a flexible 1-to-4-inch tail; 60% of sequenced short-tailed cats carry the identical Manx allele, heterozygous only, and every standard disqualifies a fully absent tail) and the Pixie-bob (8 of 14 sequenced short-tailed cats share the same allele).

In the entirely unrelated HES7 camp: the Japanese Bobtail (a kinked pompom, always present, its own confirmed dominant mutation) and the Kurilian Bobtail, whose genetics are the fancy's best open case. There, the Manx gene has been ruled out by sequencing, the Japanese Bobtail's variant is present in the breed without the final causality test, and the file stays honestly open. A fifth name you may meet, the Mekong Bobtail, is a real, distinct pointed breed recognized in other registries, not a variant of any of these.

Most tailless cats outside a breeder's program are not Manx. They are ordinary cats with a naturally short-tailed ancestry, or cats that lost the tail to injury and healed. Tail amputation after an accident is a common, well-tolerated surgery, and cats adapt their balance remarkably well afterwards. The marketplace version of this trap is documented on our own pages: listings tagged with a bobtail breed name have turned out, by their own descriptions, to be crosses of something else entirely. A pedigree is paperwork, not a silhouette.

One health note, stated the way the registries state it. The welfare questions around tailless breeding attach to the fully tailless extreme. That is why the bobtail breeds' standards all require a tail and disqualify its absence, and why some registries hold tail-mutation breeds at provisional recognition tiers pending welfare evidence. If a cat of yours has a tail injury, or a tailless cat shows hind-end weakness or litter-box changes, that is a vet visit, not a breed question.