Progressive retinal atrophy (XL-PRA)

The progressive retinal atrophy (PRA) is an inherited eye disorder leading to a degeneration of the photoreceptor cells of the retina. Initially, a loss of function of the rod cells is observed proceeding in night blindness and decreased adaptation of vision. The so-called X-linked PRA is a special form in contrast to other PRA forms, since the associated mutation is located on the X chromosome. As male dogs have only one X chromosome, they are always affected if the gene is mutated. In female dogs, both gene copies have to be mutated in order to show symptoms. First symptoms usually occur at the age of three to five years