Researchers from the University of Pennsylvania’s School of Veterinary Medicine and their colleagues have developed a treatment for X-Linked Retinitis Pigmentosa (XLRP), a form of Progressive Retinal Atrophy (PRA), in dogs. Their success in treating the initial study group also holds promise for curing XLRP in humans.
Understanding Progressive Retinal Atrophy or Retinitis Pigmentosa
To prevent confusion, we’ll use the term Retinitis Pigmentosa (RP), as canine PRA includes essentially the same types of genetic mutation as human RP.
Here’s how it works:
A healthy retina converts the light coming into the eye into images, which travel the optic nerve to the brain. In the case of RP, the retina either fails to continue to develop, or degenerates at an early stage. Loss of night vision is often the first sign of RP in dogs.
The genetic mutation which causes this may be autosomal recessive (two copies of the defective gene must be present), autosomal dominant (only one defective gene is necessary to cause the problem) or X-linked (the defect is found on an X chromosome).
The XLRP form of RP in dogs is found in Siberian huskies, but is rare in other breeds. An autosomal recessive genetic mutation is more common in other dogs. The results of this XLRP study are particularly encouraging for human medicine as XLRP is more common in people.