PRA in Basenjis

Progressive Retinal Atrophy (PRA)


  • Progressive Retinal Atrophy (PRA)
  • Disease was first described in the breed, Gordon Setters in 1911
  • Now effects over 100 breeds of dogs with a different PRA segregating in just one or a few breeds
  • PRA is a disease that is hereditary and leads to blindness in affected animals
  • It affects the retina of the eye, making them see light differently
  • PRA is actually a term used to describe a group of retinal diseases that get worse over time
  • It is a severe problem for dogs because it gets worse as time progresses, going from night blindness to blindness during the day and complete blindness if they live long enough

Genetic Transmission

  • PRA is hereditary as mentioned previously
  • Most PRA's are autosomal recessive so it may be in a blood line without showing up for a few litters
  • Additionally there are PRA's that are found to be X-linked
  • There are several genes that have been found to be associated with PRA's but not all have been found
  • In Basenjis, the SAG (S-antigen) gene is the gene that carries PRA disease
  • A non-stop mutation of this gene was found in 2013 that led to a translation of 25 excessive amino acids
  • Basenji with PRA have two copies of the effected gene (PP), carriers have one copy (PN) and unaffected and non-carriers have no effected genes (NN)

Problems With Diagnosing PRA in Dogs

  • PRA in Basenjis is not usually noticed until 5-7 years of age
  • Symptoms are hard to notice, such as thinning of retina
  • Different stages in some dogs: loss of rod and cone photoreceptor-mediated function happens in stage 2 and 3 of the disease, night blindness happened late in stage 2, a decrease in day vision happened in stage 3 and a loss of photoreceptor cells occurred in stage 3
  • Night blindness is first symptom usually so an owner may notice a dog halting when walking into a dark place
  • Dilation or enlargement of the pupil can be seen since the dog's eye is trying to let more light in
  • Cataracts can also appear
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Finding and "Treating" PRA

  • PRA is not treatable
  • Fortunately, the disease comes slowly so dogs have time to adjust themselves
  • If you think your dog has symptoms of PRA, tests can be done by a veterinarian
  • An electroretinography, which measures electrical responses of the retina, can be used to see if it is functioning properly

Preventing the Spread of PRA

  • Genetic tests are available to prevent breeding of affected dogs
  • DNA tests run for about $65 but it only tests for the form that is known in Basenjis so the animal could still have PRA that isn't the same form that a test is made for
  • Spay and neuter dogs if you know they are carriers of the disease
  • Request a DNA test before you buy a dog of your own


Genetic testing should be required before purchasing any dog breed as there are many affected species and since the disease in inherited and usually autosomal recessive, the dog can still carry it without being affected. Along with this, it is hard to notice for a number of years usually so it could go unnoticed long after you buy an animal. Spaying or neutering the species should be required if testing comes back positive so that the spread can be limited as much as possible.

Discussion Point:

Do you think that only preventing the spread of PRA by spaying and neutering affected animals and performing DNA tests is enough to limit the spread of this disease? Why or why not?


Ahonen, Saija J., Meharji Arumilli, and Hannes Lohi. "A CNGB1 Frameshift Mutation in Papillon and Phalene Dogs With Progressive Retinal Atrophy." Plos ONE 8.8 (2013): 1-8. Web. 4 May 2015. Available From:

Genomia genetic laboratory. "PRA is Basenji (Bas-PRA)." (2015). Web. 4 May 2015. Available from:

Gomes, D., et al. "Generalized Progressive Retinal Atrophy in Cocker Spanial Dogs." Scielo. August 2013. Web. 4 May 2015. Available from:

Paw Print Genetics. "Progressive Retinal Atrophy (Basenji Type)." Genetic Veterinary Sciences, Inc. (2015). Web. 4 May 2015. Available From:


Blogg, Rowan and Pik, Noam. "PRA." ASAP Laboratory. (2012). Web. 4 May 2015. Available from:


BCOA. "About the Basenji Club of America." (2011). Web. 4 May 2015. Available From:

Cooper, Ann E., et al. "A Novel Form of Progressive Retinal Atrophy in Swedish Vallhund Dogs." Plos One: (2014). Web. 4 May 2015. Available From: