Glaucoma-causing mutations are also reproducibly associated with height in two domestic dog breeds: selection for short stature may have contributed to increased prevalence of glaucoma.

BACKGROUND

In humans, mutations are known to cause Weill-Marchesani-like syndrome, which is characterised by lenticular myopia, ectopia lentis, glaucoma, spherophakia, and short stature. Breed-specific homozygous mutations in are associated with primary open angle glaucoma (POAG) in several dog breeds, including the Petit Basset Griffon Vendeen (PBGV) and Shar Pei (SP). We hypothesised that these mutations are associated with short stature in these breeds.

METHODS

Two hundred thirty-three PBGV and 66 SP were genotyped for their breed-specific mutations. The height of each dog was measured at the withers. We used linear (per allele) regression to assess the association between mutations and height as a continuous variable, and linear regression and likelihood ratio tests to assess the shape of the association by comparing a general model with a linear (per allele) model.

RESULTS

The adjusted mean heights of affected, carrier, and clear PBGV were 33.49 cm ( = 21, 95% CI 32.78-34.19 cm), 34.88 cm ( = 85, 95% CI 34.53-35.25 cm), and 34.92 cm ( = 121, 95% CI 34.62-35.21 cm), respectively. The mean heights of affected, carrier, and clear SP were 43.96 cm ( = 9, 95% CI 41.88-46.03 cm), 47.56 cm ( = 28, 95% CI 45.50-48.63 cm), and 48.95 cm ( = 23, 95% CI 47.80-50.11 cm), respectively. There was a significant difference between the height of affected and clear animals in the PBGV ( = 0.001) and the SP ( = < 0.0001).

CONCLUSIONS

POAG mutations are significantly associated with height in these breeds.