Screw tail


Screw tail is a type of natural short tail that can be found in Bulldogs, French Bulldogs and Boston Terriers. It is different from the natural short tail seen in Pembroke Welsh Corgis because the bones in the short tail usually make a kinked rather than straight shape.

The gene that causes screw tail (the DVL2 gene) does not just change the shape of the tail. It contributes to the brachycephalic skull type that gives the screw tail dog breeds extremely short noses. Dogs with two copies of this gene can also have a range of abnormalities in their spinal vertebrae, including hemivertebrae, which is why we characterise this trait as a disorder rather than just an appearance trait.

There is a lot of natural variation in the way the screw tail gene is expressed. Testing can be required to see how many copies of the gene are present in your dog.

Gene or region and technical reference

Gene: DVL2 (causative). Reference: Mansour et al (2018)

Reported alleles

n. Test developed using artificial DNA, animal controls.

ST. Test developed using artificial DNA, animal cases.

Panels: groups of tests that are often ordered together

This test is not in any panels.

Order tests

There is a one-off sample processing fee of $40 per animal plus the cost of your tests.

How many animals are you testing? Discount or society code:


Colour panels

$24 B locus ... more

$16 D locus ... more

$16 E locus ... more

Working dogs

$59 Australian Kelpie panel ... more

$26 Working dog CA ... more

$54 Working dog core panel ... more

Good looks

Coat characteristics

$9 Coat length L (common form) (L) ... more

$9 Coat length L2 (L2) ... more

$9 Curly coat ... more

$9 Improper coat ... more

Good health

Australian Kelpies

$14 Intestinal lipid malabsorption (ILM) ... more

Good looks

Coat colour

$9 B locus brown (bc allele) (bc) ... more

$9 B locus brown (bd allele) (bd) ... more

$9 B locus brown (bs allele) (bs) ... more

$9 D locus dilute d (common type) (d) ... more

$9 D locus dilute d2 (Chow Chow type) (d2) ... more

$9 E locus melanistic mask ... more

$9 E locus red/black ... more

$9 K locus dominant black ... more

Good health

Multiple breeds

$14 Airways oedema ... more

$14 Degenerative myelopathy (DM) ... more

$14 Progressive retinal atrophy - PRCD (PRA-PRCD) ... more

$14 Screw tail

Working dogs

$14 Cerebellar abiotrophy marker (LINGO3) (CA: LINGO3) ... more

$14 Cerebellar abiotrophy marker (VMP1) (CA: VMP1) ... more

$14 Collie eye anomaly (CEA) ... more

$14 Trapped neutrophil syndrome (TNS) ... more

Tests can be in the list more than once when the gene in question has more than one effect. It is OK to select the same test once or more than once, the price is the same.