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Reviewed October 2008

What is the official name of the PRPH2 gene?

The official name of this gene is “peripherin 2 (retinal degeneration, slow).”

PRPH2 is the gene's official symbol. The PRPH2 gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the PRPH2 gene?

The PRPH2 gene (also known as RDS) provides instructions for making a protein called peripherin 2. This protein plays an important role in normal vision. Peripherin 2 is found in the retina, the light-sensitive tissue that lines the back of the eye. This protein is essential for the normal function of specialized cells called photoreceptors that detect light and color. Within these cells, peripherin 2 is involved in the formation and stability of structures that contain light-sensing pigments.

How are changes in the PRPH2 gene related to health conditions?

vitelliform macular dystrophy - caused by mutations in the PRPH2 gene

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.

other retinal dystrophies - caused by mutations in the PRPH2 gene

Mutations in the PRPH2 gene cause a variety of other retinal disorders. Each of these conditions involves a slow degeneration of photoreceptor cells, leading to progressive vision loss. A total of more than 100 mutations in the PRPH2 gene have been identified. Many of these mutations cause autosomal dominant retinitis pigmentosa, an eye disease that first disrupts night vision and side (peripheral) vision and eventually may result in blindness. PRPH2 mutations also cause a group of retinal 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, 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.

Genetics Home Reference provides information about retinitis pigmentosa, which is also associated with changes in the PRPH2 gene.

Where is the PRPH2 gene located?

Cytogenetic Location: 6p21.1

Molecular Location on chromosome 6: base pairs 42,696,595 to 42,722,989

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The PRPH2 gene is located on the short (p) arm of chromosome 6 at position 21.1.

The PRPH2 gene is located on the short (p) arm of chromosome 6 at position 21.1.

More precisely, the PRPH2 gene is located from base pair 42,696,595 to base pair 42,722,989 on chromosome 6.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about PRPH2?

You and your healthcare professional may find the following resources about PRPH2 helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the PRPH2 gene or gene products?

  • CACD2
  • peripherin 2, homolog of mouse
  • peripherin, photoreceptor type
  • RDS
  • retinal degeneration, slow
  • retinal degeneration slow protein
  • Tetraspanin-22
  • TSPAN22

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding PRPH2?

amino acid ; autosomal ; autosomal dominant ; epithelium ; gene ; mutation ; peripheral ; photoreceptor ; pigment ; protein ; retina ; tissue

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.

References (12 links)


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.

Reviewed: October 2008
Published: February 8, 2016