Test Detail

Variant of the DVL2 gene (dishevelled-2, Wnt pathway) associated with caudal vertebral malformations (screw tail) and a bulldog-type brachycephalic phenotype, within the spectrum of human Robinow syndrome. It is a developmental skeletal trait, not a platelet disease: this test does NOT evaluate macrothrombocytopenia or any coagulopathy. The variant segregates with the phenotype in an autosomal recessive, fully penetrant manner in several breeds.

Documented in English and French Bulldog, Boston Terrier, Shih Tzu, Pit Bull, American Bulldog, AmStaff, Dogue de Bordeaux, Pug and crossbreeds (OMIA:002186). Population carrier frequencies: limited data.

- Test the breeding animals of affected breeds before mating.\n- Do not mate two carriers: 25 %% risk of homozygotes with vertebral malformations.\n- A carrier can be mated to a clear animal; test the offspring intended for breeding.\n- In homozygotes, veterinary monitoring of the spine, breathing and heart (the links with BOAS and heart disease are hypotheses under study, not a direct indication).\n- This test does not evaluate platelets: in the presence of thrombocytopenia, investigate the specific causes (TUBB1, GP9, MYH9, immune-mediated).

Differential diagnosis of vertebral malformations (hemivertebrae of other aetiologies) and of brachycephaly. Screw tail is a morphological trait with potential orthopaedic and neurological consequences, not a coagulopathy: do not request a blood count looking for MTC due to this variant. Imaging tests (X-ray/CT) characterise the malformations.

1. Mansour TA et al. 2018, asociación de genoma completo en 100 perros identifica mutación con cambio de marco en DVL2 y fenotipo tipo Robinow (PMID 30521570)
2. Niskanen JE et al. 2021, la variante DVL2 contribuye al fenotipo braquicéfalo y anomalías vertebrales caudales (PMID 33599851)
3. OMIA:002186 Cola en tornillo / síndrome tipo Robinow (DVL2)