Progressive Retinal Atrophy (PRA) in the Basenji

Quick Summary

Progressive retinal atrophy (PRA) is characterized by degeneration of the retina resulting in progressive vision loss leading to total blindness. This Basenji PRA is caused by a mutation in the S-antigen (SAG) gene.

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Phenotype: Affected adult dogs begin to display night blindness (vision loss under low light) that gradually progresses to complete blindness. Many Basenjis, however, do maintain adequate daylight vision for many years.

Mode of Inheritance: Autosomal recessive

Alleles: N = Normal, PRA = Progressive retinal atrophy (Basenji variant)

Breeds appropriate for testing: Basenji

Explanation of results:
•    Dogs with N/N genotype are expected to not have this Basenji progressive retinal atrophy variant. They cannot transmit this PRA allele to any of their offspring.
•    Dogs with N/PRA genotype have one copy of this PRA allele and are expected to not have progressive retinal atrophy but are carriers. They will transmit this PRA allele to 50% of their offspring. Matings between two carriers of PRA may, on average, produce 25% of puppies with progressive retinal atrophy.
•    Dogs with PRA/PRA genotypes are homozygous for this PRA allele and will display signs of progressive retinal atrophy.

Turnaround Time
at least 15 business days; may be delayed beyond 15 business days if sample requires additional testing, or a new sample is requested.

$55 single test per animal ($5 discount on 3 or more dogs)
$25 as additional health test on same animal

Sample Collection

Dog DNA tests are carried out using cells brushed from your dog's cheeks and gums. The preferred cytology brushes are sent to you by mail, or you may provide your own brushes. For accepted alternative brushes, click here

We recommend waiting until puppies are at least three weeks old before testing.


Dog having its cheeks and gums brushed for DNA samples
Cheek and gum brushing technique for canine DNA sample collection


  1. Make sure the dog has not had anything to eat or drink for at least 1 hour prior to collecting sample.
  2. When swabbing puppies, isolate each puppy from the mother, littermates and any shared toys for 1 hour prior to swabbing. Puppies should not have nursed or eaten for 1 hour prior to collecting sample.
  3. If collecting samples from more than one dog, make sure to sample one dog at a time and wash your hands before swabbing another dog.
  4. Label brush sleeve with name or ID of dog to be sampled.
  5. Open brush sleeve by arrow and remove one brush by its handle.
  6. Place bristle head between the dog’s gums and cheek and press lightly on the outside of the cheek while rubbing or rotating the brush back and forth for 15 seconds.
  7. Wave the brush in the air for 20 seconds to air dry.
  8. Insert brush back into sleeve.
  9. Repeat steps 5 - 8 for each unused brush in sleeve on a fresh area of cheek and gums. Make sure to use and return all brushes sent by the VGL. In most cases, it will be 3 brushes per dog. If using interdental gum brushes, please note that the VGL requires 4 brushes per dog and only moderate or wide interdental gum brushes are accepted.
  10. Do not seal brushes in sleeve.
  11. Place all samples in an envelope and return to the address provided.


  • Do not collect saliva/drool – the key to obtaining a good sample is getting cheek cells on the swab
  • Do not rub swab on the dog’s tongue or teeth – this will result in poor quality sample
  • Do not collect a sample from a puppy that has recently nursed – the mother’s genetic material can rub off on the puppy’s mouth and contaminate the sample
Additional Details

Progressive retinal atrophy (PRA) is a term used to describe a group of inherited disorders of the retina, characterized by progressive retinal degeneration and consequent blindness. More than 20 mutations in various genes have been associated with PRA in dogs. A non-stop genetic variant in the S-antigen (SAG) gene has been identified as the cause of an adult onset progressive retinal atrophy that affects Basenjis.

This PRA disorder is inherited in an autosomal recessive manner, meaning that a dog must have two copies of this PRA allele to be affected. Affected dogs begin to display vision loss in dim light in adulthood. While many Basenjis are able to maintain daylight vision for many years, the disorder typically progresses to complete blindness. 

Testing recommendations: DNA testing for progressive retinal atrophy can determine the genetic status of dogs. Dogs with one copy of the PRA allele are normal but are carriers. Matings between two carrier dogs may, on average, produce 25% of puppies with progressive retinal atrophy.