T-Locus (tailless)


Turnaround: 10-15 business days

Not sure how the process works? Have a read of our Frequently Asked Questions.

The T-Locus is a region of your dog's DNA which determines whether they have a genetic bobtail (tailless) or not.

The bobtail is caused by a mutation in the T gene. Bobtail is autosomal dominant meaning that a dog only needs to inherit one copy of the mutation to have a genetic bobtail. Dogs which inherit two copies of the bobtail mutation will die in utero and therefore not survive to birth.


Your results will be reported as normal or bobtail with the following interpretations.

Normal - normal length tail
Bobtail - genetic bobtail


Scientific references:

Hytonen MK, Grall A, Hedan B, Dreano S, Seguin SJ, Delattre D, Thomas A, Galibert F et al (2009) Ancestral T-box mutation is present in many, but not all, short-tailed dog breeds. J. Hered. 100, 236-240