Progressive Retinal Atrophy

in Basenjis


Progressive Retinal Atrophy--abbreviated as PRA--is a condition diagnosed in certain breeds of dogs, such as Basenjis. It is also seen, albeit rarely, in cats. PRA is characterized by the bilateral degeneration of the retina. The retina begins to deteriorate later in life (between 3 and 13 years of age), resulting first in night blindness. Then, if the dog lives long enough, it progresses to the deterioration of day vision, resulting in total blindness.

Early Symptoms to Look For

There are some early signs of PRA that can be recognized by owners. The first signs of PRA are that a dog is hesitant to go out at night. They may appear to be afraid of the dark, will stay close to you are night, and may appear short sighted. Again, this is because the first stage of PRA is night blindness. Other subtle signs include stumbling while going down stairs or going much more slowly/cautiously than in the past.

Genetic Inheritance

Progressive Retinal Atrophy is inherited as an autosomal recessive trait in nearly all breeds. There is a great discrepancy between genotype and phenotype for PRA. Note that the PRA gene is denoted by the letter p. A Basenji with homozygous dominant alleles (PP) is not a carrier of the disease and does not display signs of it. A heterozygous genotype (Pp) is a carrier of the disease yet is unaffected by it. A homozygous recessive (pp) dog is both a carrier of the disease and affected by it. Two heterozygous parent Basenjis have a 1 in 4 chance of having a puppy that will suffer PRA.

In the video below, the speaker explains these genotypes and phenotypes in dogs (from 8:21 to 9:10).

Building Better Dogs - Mike Goddard (1 of 4)


There is no treatment for PRA, so the only way to combat the spread of this disease is to avoid breeding carriers of this disease. A genetic test is the only way to know whether a dog is a carrier without having to breed it and wait to find out if it produces a PRA-affected offspring.

Basenji breeders were once cautious when it came to the spread of PRA. A dog that was even slightly suspected of being a carrier was not bred. However, the standards of breeders have gone downhill in recent years, and carelessness has led to a rise in PRA carriers and affected dogs.

The ability to DNA test a dog for the genes related to PRA makes the eradication of this disease more feasible for breeders today by taking out the guesswork.


While there are some regulations on breeders--such as humane treatment under the Animal Welfare Act--it is not difficult for unregulated puppy mills to crop up. Even if registered breeders back the eradication of Progressive Retinal Atrophy, illegal puppy mills can easily undermine their efforts by breeding any dog who carries or suffers from PRA. What can be done to go forward the eradication effort and ultimately succeed?