In humans, a tiny area in the center of the retina called the fovea is critically important to viewing fine details. Densely packed with cone photoreceptor cells, it is used while reading, driving and gazing at objects of interest. Some animals have a similar feature in their eyes, but researchers believed that among mammals the fovea was unique to primates until now.
University of Pennsylvania vision scientists report that dogs, too, have an area of their retina that strongly resembles the human fovea. What's more, this retinal region is susceptible to genetic blinding diseases in dogs just as it is in humans.
"It's incredible that in 2014 we can still make an anatomical discovery in a species that we've been looking at for the past 20,000 years and that, in addition, this has high clinical relevance to humans," said William Beltran, an assistant professor of ophthalmology in Penn's School of Veterinary Medicine and co-lead author of the study with Artur Cideciyan, research professor of ophthalmology in Penn's Perelman School of Medicine.
"It is absolutely exhilarating to be able to investigate this very specialized and important part of canine central vision that has such unexpectedly strong resemblance to our own retina," Cideciyan added.
Additional coauthors included Penn Vet's Karina E. Guziewicz, Simone Iwabe, Erin M. Scott, Svetlana V. Savina, Gordon Ruthel and senior author Gustavo D. Aguirre; Perelman's Malgorzata Swider, Lingli Zhang, Richard Zorger, Alexander Sumaroka and Samuel G. Jacobson; and the Penn School of Dental Medicine's Frank Stefano.
The paper was published in the journal PLOS ONE.
The word "fovea" comes from the Latin meaning "pit," owing to the fact that in humans and many other primates, the inner layers of the retina are thin in this area, while the outer layers are packed with cone photoreceptor cells. It is believed that this inner layer thinning allows the foveal cone
|Contact: Katherine Unger Baillie|
University of Pennsylvania