About RETINITIS PIGMENTOSA

A man's face looking at the words saying "Genetic variants in more than 60 genes can cause the disease."
Retinitis Pigmentosa (RP) is a rare genetic disorder characterized by progressive vision loss from dying cells in the retina.

RP is the most common disease group in the inherited retinal disease (IRD) family and is also known as rod dystrophy or rod-cone dystrophy.
Genetic variants found in more than 60 genes can cause various types of RP.

PREVALENCE / ONSET

Map background with the silhouette of a boy and words saying "1 in 3,000 to 1 in 5,000 people worldwide."

Prevalence

The prevalence of RP is 1 in 3,000 to 1 in 5,000 worldwide.

Onset

Symptoms of RP are usually present from childhood. Since there are many types of RP, the severity and rate of worsening of symptoms vary from person to person

SYMPTOMS

Six symptoms of Retinitis pigmentosa: Loss of night vision, Gradual loss of side vision(tunnel vision), Loss of central vision, Problems with color vision, photophobia, photopsia

DIAGNOSIS

RP is diagnosed based on tests using an ophthalmoscope, electroretinogram, and visual field test. Then, the type of RP is confirmed with genetic tests.

As gene-phenotype correlations continue to be revealed through research and novel therapies continue to be developed, the importance of molecular diagnosis is growing.

Ophthalmoscope

With a special drop to widen your pupil, the doctor can look into your eye. If there are dark spots on your retina, there are possibilities of having RP.

Electroretinogram

Using a special contact lens or a film of gold foil, the doctor can measure how your retina responds to light.

Visual Field Test

With a tabletop machine that shows objects or lights on the side of the vision, it can create a map of your visual sight.

Genetic Testing

By using genetic tests, causal genes can be detected and selected to give an accurate diagnosis. Accurate diagnosis is necessary to give an accurate treatment.

In a UK research study, 135 common pathogenic variants were found in 4,326 patients with IRD, and a list of 20 most frequently shared genes between the patients was released. 12 of them - RPGR, PRH2, RP1, RHO, CRB1, PRPF31, RPE65, EYS, GUCY2D, PROM1, RDH12 - have been found in previous research literature to be closely associated with RP.

Because there are many genes that can cause eye disease, the American Academy of Ophthalmology recommends genetic testing for accurate diagnosis and appropriate treatment. However, the majority of clinical ophthalmologists are not familiar with diagnosis through genetic testing.

INHERITANCE PATTERN

Circle shape to explain that Retinitis pigmentosa can inherit in autosomal recessive, autosomal domimant, and X-linked pattern, depending on the causative gene.
Since there are more than 60 different RP types, three different inheritance patterns are possible depending on the type; X-linked, autosomal recessive, and autosomal dominant.

TREATMENTS

  1. ic-treatments-black@3x-3
  2. RP, in general, is currently incurable. However, there are available treatments that aim to treat certain diseases in the RP group or slow the progression of disease.

Voretigene neparvovec-rzyl (Luxturna)

Voretigene neparvovec-rzyl (Luxturna) produced and marketed by Novartis and Roche is an adeno-associated virus vector-based gene therapy where intact RPE65 gene that can replace mutated autosomal recessive RPE65 gene is injected into a patient’s body. This only covers one gene of many other RP causing genes; however, this is a new possibility that could lead to many other RP treatments.

Second Sight’s Argus 2s Retinal Prosthesis System

Second Sight’s Argus 2s Retinal Prosthesis System is also an option for patients severely impacted by RP.

Special glasses (or sunglasses)

A light amber filter can be added to eyeglasses and help improve tolerance of bright lights.

Vitamin A

Some research suggests that high dosages of vitamin A can help slow the disease's progression in some people. Based on recent findings, vitamin A palmitate is recommended to RP patients.

Many studies and clinical trials for the development of new treatments are in progress. You can check their schedules and progress through Centerwatch or Foundation Fighting Blindness.

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