Van den Ende–Gupta Syndrome (VDEGS) in Wire Fox Terriers
Van den Ende–Gupta Syndrome (VDEGS) is a genetic disorder affecting the Wire Fox Terrier dog breed. The disorder is characterized by craniofacial and skeletal manifestations, mainly malar and /or maxillary hypoplasia, distinctive nose, and long slender bones of feet. The same-named syndrome is affecting human patients as well, with same symptoms and mutation in the same gene as in the canine form of the disorder.
Characteristics and Symptoms
Affected dogs can be recognized by their prominent underbite with short maxilla (brachygnathia superior), with a slightly convex caudodorsal border of the maxilla. The affected puppies show unilateral congenital elbow luxation and secondary ossification centers. The vertebrae number and position appears normal, but the mid-thoracic spinous processes are thinner, longer and more horizontally aligned than in healthy dogs. Adult dogs develop spinal arthritis. Affected dogs’ femurs have medial bowing of mid-shafts of the bone. The eyes appear smaller and sclera thinner than normal. Examination reveals swollen knee joints and patellar luxation. No neurological deficits were noticed. CT imaging reveals prominently deviated nasal septum to the left.
Van den Ende–Gupta Syndrome (VDEGS) in the Wire Fox Terriers is caused by a mutation in the SCARF2 gene. The mutation is caused by a 2-bp deletion in exon 6 of the SCARF2 gene, which results in a frameshift and a premature stop codon, and consequently, a truncated protein is produced.
Van den Ende–Gupta Syndrome (VDEGS) in the Wire Fox Terriers is inherited in an autosomal recessive pattern. Healthy parents of affected puppy are obligate heterozygotes and therefore carry one mutant allele. Heterozygotes have no symptoms. Dogs homozygous for the mutation will display the symptoms of the VDEGS. At conception, when mating two carrier dogs, each cub has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier.
Hytönen MK, Arumilli M, Lappalainen AK, Owczarek-Lipska M, Jagannathan V, Hundi S, et al. (2016) Molecular Characterization of Three Canine Models of Human Rare Bone Diseases: Caffey, van den Ende-Gupta, and Raine Syndromes. PLoS Genet 12(5): e1006037. https://doi.org/10.1371/journal.pgen.1006037