Trapped Neutrophil Syndrome (TNS)

Gene: VPS13B

Transmission: Autosomal recessive

For an autosomal recessive genetic disease an animal must have two copies of the mutation in question to be at risk of developing the disease.  Both parents of an affected animal must be carriers of at least one copy of the mutation.  Animals that have only one copy of the mutation are not at risk of developing the disease but are carrier animals that can pass the mutation on to future generations.

Mutation: Deletion, VPS13B gene; c.2893_2896 del. GTTT, p.(V595I fs)

Medical system: Blood

Breeds: Australian Kelpie, Border Collie

Age of onset of symptoms: between 6 to 12 months of age

Trapped Neutrophil Syndrome is a genetic disease seen in the Border Collie due to a defect in the immune system such that white blood cess (neutrophils) are not produced in sufficient quantity.  Affected puppies are usually smaller than non- affected littermates, and by age 6 to 12 weeks can show signs of fever, depression, lethargy, unsteady and clumsy walk, diarrhea and vomiting.  Since the affected puppy cannot combat bacterial infections, often they have infections of the lungs, skin, eyes and ears.  Although it possible for some dogs to show no symptoms until they turn 2 years old, more typically affected puppies die from bacterial infections by about 4 months of age.

References:

OMIA link: [1428-9615]

Donner J, Freyer J, Davison S, et al. (2023) Genetic prevalence and clinical relevance of canine Mendelian disease variants in over one million dogs.  PLoS Genet. 19(2):e1010651. [pubmed/36848397]

Zoto A, Stecklein C, Scott MA, et al. (2022) Multiorgan neutrophilic inflammation in a Border Collie with “trapped” neutrophil syndrome. J Vet Intern Med 36:2170-2176.  [pubmed/36239343]

Soh PXY, Hs WT, Khatkar M, Williamson, P. (2021) Evaluation of genetic diversity and management of disease in Border Collie dogs. Sci Rep 11:6243. [pubmed/33737533]

Hegler AK, Grooters AM, Dehghanpir SD, Gallaher RA, Gaschen LE.  (2020) Trapped Neutrophil Syndrome in a Border Collie. J Am Anim Hosp Assoc. 56(3):e56304. [pubmed/32182118]

Mizukami K, Yabuki A, Kohyama M, Kushida K et.al. (2016) Molecular prevalence of multiple genetic disorders in Border collies in Japan and recommendations for genetic counselling. Vet J 214:21-3. [pubmed/27387721]

Mason SL, Jepson R, Maltman M, Batchelor DJ. (2014) Presentation and management of trapped neutrophil syndrome (TNS) in UK Border collies. J Small Anim Pract 55:57-60. [pubmed/24032537]

Shearman, JR, Wilton AN. (2011) A canine model of Cohen syndrome: trapped neutrophil syndrome. BMC Genomics 12:258.  [pubmed/21605373]