PRPH2

Mutations in the PRPH2 gene are responsible for some cases of adult-onset vitelliform macular dystrophy. Several mutations have been identified in people with this disorder, most of which change a single protein building block (amino acid) in peripherin 2. These mutations alter the protein's structure or lead to the production of an abnormally short, nonfunctional version of the protein. When peripherin 2 is altered or missing, photoreceptors break down (degenerate) over time. This loss of photoreceptors underlies the retinal abnormalities and progressive vision loss characteristic of vitelliform macular dystrophy. It is unclear why PRPH2 mutations affect only central vision in people with this disorder.

Mutations in the PRPH2 gene can cause autosomal dominant retinitis pigmentosa, an eye disease that first disrupts night vision and side (peripheral) vision and eventually may result in blindness.  Like other retinal disorders caused by PRPH2 gene mutations, retinitis pigmentosa involves a slow degeneration of photoreceptor cells, leading to progressive vision loss.

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Mutations in the PRPH2 gene cause a variety of retinal disorders, including a group of disorders called pattern dystrophies of the retinal pigment epithelium. These disorders typically begin in mid-adulthood and are characterized by an abnormal buildup of pigment in cells underlying the retina.

Some PRPH2 mutations can cause different eye disorders in affected members of the same family. For example, researchers have reported a family with retinitis pigmentosa (described above), pattern dystrophy of the retinal pigment epithelium, and retinitis punctata albescens (an eye disorder similar to retinitis pigmentosa) in different individuals with the same PRPH2 mutation. It is unclear why mutations in this gene cause such a wide range of retinal abnormalities.