Rodrigo Gutierrez-Quintana (University of Glasgow) and Tosso Leeb and Matthias Christen (University of Bern) have been investigating the genetics of a disease called exercise induced paroxysmal movement disorder (PMD) in Weimaraners. The disease affects young Weimaraner puppies (younger than 8 months of age) who present with episodic gait abnormalities characterised by muscle stiffness, arched back and wobbliness. The episodes last 5-15 minutes and are triggered by excitement and/or exercise. In between the episodes the dogs appear normal. The investigations started with the diagnosis of a small number of affected puppies from the UK and have progressed to the identification of the causal genetic defect.
Working with Rodrigo and Tosso, the Kennel Club Genetics Centre (KCGC) has genotyped DNA from 26 UK Weimaraners that we have in our research sample collection and have identified two dogs that are heterozygous (carriers) of the causal disease allele. The disease is recessive, meaning heterozygous dogs will not be clinically affected but will pass the disease allele (mutation) to half of their offspring. Dogs that inherit a copy of the disease allele from each parent will be affected, assuming the candidate variant is indeed the cause of this disease. The frequency of the disease allele in the 26 dogs is just under 4%; if this is representative of the UK population we expect 1 or 2 dogs a year to be affected (assuming random breeding with respect to the variant).
For any enquiries about the research please contact the Kennel Club Genetics Centre.
These findings have been submitted to a scientific journal for peer-review. Meanwhile a DNA test based on the PMD variant is exclusively available from Canine Genetic Testing.
In recent years multiple dogs of the Old English Sheepdog (OES) breed have been diagnosed with an ocular (eye) disease that can affect multiple parts of the eye and is therefore known as multiocular defect (MOD). Most affected dogs suffer from cataracts, but additional abnormalities can include any of the following:
- microphakia (small lens),
- lens coloboma (a hole in the lens),
- macrophthalmos (enlarged globe),
- retinal detachment,
- vitreopathy and
- retinal degeneration
The Kennel Club Genetics Centre (KCGC) at the University of Cambridge has been investigating the genetics of MOD in the Old English Sheepdog breed. By analysing the whole genome sequence of an affected OES generated via the Give a Dog a Genome Project, the team were able to identify the likely causal variant for MOD. The variant is a single nucleotide substitution located within an exon (the part of the gene that creates the protein) of a gene called COL11A1. The variant is predicted to change the amino acid sequence of the corresponding protein in a way that damages the protein and is therefore a ‘missense’ variant. It has a dominant mode of inheritance as dogs with either one or two copies of the variant are clinically affected by MOD.
Mutations in COL11A1 have been reported to cause a dominant form of Stickler Syndrome (STL2) in humans, which shares clinical features observed in MOD affected OES. There is evidence that affected dogs with 2 copies of the variant, i.e. homozygous for the variant have a more severe phenotype. The disease has an early age of onset.
For enquiries about the research, contact the Kennel Club Genetics Centre.
The results of this study are currently being prepared for submission to a scientific, peer-reviewed journal. In the meantime, a DNA test for MOD In OES Is exclusively available from Canine Genetic Testing, and can either be bought as a single test or as part of a bundle of discounted tests (available from 9 January 2023).