Retinitis pigmentosa
Encyclopedia
Retinitis pigmentosa is a group of genetic eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...

 conditions that leads to incurable blindness. In the progression of symptoms for RP, night blindness
Nyctalopia
Nyctalopia is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases. Night blindness may exist from birth, or be caused by injury or malnutrition...

 generally precedes tunnel vision
Tunnel vision
Tunnel vision is the loss of peripheral vision with retention of central vision, resulting in a constricted circular tunnel-like field of vision.- Medical / biological causes :Tunnel vision can be caused by:...

 by years or even decades. Many people with RP do not become legally blind
Blindness
Blindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...

 until their 40s or 50s and retain some sight all their lives. Others go completely blind from RP, in some cases as early as childhood. Progression of RP is different in each case.

RP is a type of progressive retinal dystrophy
Retinopathy
Retinopathy is a general term that refers to some form of non-inflammatory damage to the retina of the eye. Frequently, retinopathy is an ocular manifestation of systemic disease.-Pathophysiology:Causes of retinopathy are varied:...

, a group of inherited disorders in which abnormalities of the photoreceptors (rod
Rod cell
Rod cells, or rods, are photoreceptor cells in the retina of the eye that can function in less intense light than can the other type of visual photoreceptor, cone cells. Named for their cylindrical shape, rods are concentrated at the outer edges of the retina and are used in peripheral vision. On...

s and cone
Cone cell
Cone cells, or cones, are photoreceptor cells in the retina of the eye that are responsible for color vision; they function best in relatively bright light, as opposed to rod cells that work better in dim light. If the retina is exposed to an intense visual stimulus, a negative afterimage will be...

s) or the retinal pigment epithelium (RPE) of the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...

 lead to progressive visual loss. Affected individuals first experience defective dark adaptation or nyctalopia
Nyctalopia
Nyctalopia is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases. Night blindness may exist from birth, or be caused by injury or malnutrition...

 (night blindness), followed by reduction of the peripheral visual field
Peripheral vision
Peripheral vision is a part of vision that occurs outside the very center of gaze. There is a broad set of non-central points in the field of view that is included in the notion of peripheral vision...

 (known as tunnel vision) and, sometimes, loss of central vision late in the course of the disease.

Signs

Mottling of the retinal pigment epithelium with black bone-spicule pigmentation is typically indicative (or pathognomonic
Pathognomonic
Pathognomonic is a term, often used in medicine, that means characteristic for a particular disease. A pathognomonic sign is a particular sign whose presence means that a particular disease is present beyond any doubt...

) of retinitis pigmentosa. Other ocular
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...

 features include waxy pallor
Pallor
Pallor is a reduced amount of oxyhaemoglobin in skin or mucous membrane, a pale color which can be caused by illness, emotional shock or stress, stimulant use, lack of exposure to sunlight, anaemia or genetics....

 of the optic nerve
Optic nerve
The optic nerve, also called cranial nerve 2, transmits visual information from the retina to the brain. Derived from the embryonic retinal ganglion cell, a diverticulum located in the diencephalon, the optic nerve doesn't regenerate after transection.-Anatomy:The optic nerve is the second of...

 head, attenuation (thinning) of the retinal
Retinal
Retinal, also called retinaldehyde or vitamin A aldehyde, is one of the many forms of vitamin A . Retinal is a polyene chromophore, and bound to proteins called opsins, is the chemical basis of animal vision...

 vessels, cellophane maculopathy
Maculopathy
A maculopathy is any pathological condition of the macula, an area at the centre of the retina that is associated with highly sensitive, accurate vision.-Examples Of Maculopathies:...

, cystic macular edema
Edema
Edema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...

 and posterior subcapsular cataract
Cataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...

.

Diagnosis

The diagnosis
Medical diagnosis
Medical diagnosis refers both to the process of attempting to determine or identify a possible disease or disorder , and to the opinion reached by this process...

 of retinitis pigmentosa relies upon documentation of progressive loss in photoreceptor cell function by electroretinography
Electroretinography
Electroretinography measures the electrical responses of various cell types in the retina, including the photoreceptors , inner retinal cells , and the ganglion cells. Electrodes are usually placed on the cornea and the skin near the eye, although it is possible to record the ERG from skin electrodes...

 (ERG) and visual field
Visual field
The term visual field is sometimes used as a synonym to field of view, though they do not designate the same thing. The visual field is the "spatial array of visual sensations available to observation in introspectionist psychological experiments", while 'field of view' "refers to the physical...

 testing.

The mode of inheritance
Inheritance
Inheritance is the practice of passing on property, titles, debts, rights and obligations upon the death of an individual. It has long played an important role in human societies...

 of RP is determined by family history. At least 35 different gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s or loci
Locus (genetics)
In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map...

 are known to cause "nonsyndromic RP" (RP that is not the result of another disease or part of a wider syndrome
Syndrome
In medicine and psychology, a syndrome is the association of several clinically recognizable features, signs , symptoms , phenomena or characteristics that often occur together, so that the presence of one or more features alerts the physician to the possible presence of the others...

).

DNA testing is available on a clinical basis for: (autosomal recessive, Bothnia type RP) (autosomal dominant, RP1) (autosomal dominant, RP4) (autosomal dominant, RP7) (autosomal dominant, RP13) (autosomal dominant, RP18)
  • CRB1
    CRB1
    Crumbs homolog 1 is a protein that in humans is encoded by the CRB1 gene.This gene encodes a protein which is similar to the Drosophila crumbs protein and localizes to the inner segment of mammalian photoreceptors...

     (autosomal recessive, RP12) (autosomal recessive, RP19) (autosomal recessive, RP20)


For all other genes, molecular genetic testing
Genetic testing
Genetic testing is among the newest and most sophisticated of techniques used to test for genetic disorders which involves direct examination of the DNA molecule itself. Other genetic tests include biochemical tests for such gene products as enzymes and other proteins and for microscopic...

 is available on a research basis only.

RP can be inherited in an autosomal dominant, autosomal recessive, or X-linked
Sex linkage
Sex linkage is the phenotypic expression of an allele related to the chromosomal sex of the individual. This mode of inheritance is in contrast to the inheritance of traits on autosomal chromosomes, where both sexes have the same probability of inheritance...

 manner. X-linked RP can be either recessive
Recessive
In genetics, the term "recessive gene" refers to an allele that causes a phenotype that is only seen in a homozygous genotype and never in a heterozygous genotype. Every person has two copies of every gene on autosomal chromosomes, one from mother and one from father...

, affecting primarily only males, or dominant, affecting both males and females, although males are usually more mildly affected. Some digenic (controlled by two genes) and mitochondrial forms have also been described.

Genetic counseling
Genetic counseling
Genetic counseling or traveling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning...

 depends on an accurate diagnosis, determination of the mode of inheritance in each family, and results of molecular genetic testing.

Associations

Retinitis pigmentosa is seen in a variety of diseases, so the differential of this sign alone is broad.
  • RP combined with deafness (congenital or progressive) is called Usher syndrome
    Usher syndrome
    Usher syndrome is a relatively rare genetic disorder that is a leading cause of deafblindness and that is associated with a mutation in any one of 10 genes. Other names for Usher syndrome include Hallgren syndrome, Usher-Hallgren syndrome, rp-dysacusis syndrome and dystrophia retinae dysacusis...

    .
  • RP combined with opthalmoplegia, dysphagia, ataxia, and cardiac conduction defects is seen in the mitochondrial DNA disorder Kearns-Sayre syndrome
    Kearns-Sayre syndrome
    Kearns–Sayre syndrome also known as oculocraniosomatic disease or Oculocraniosomatic neuromuscular disease with ragged red fibers is a mitochondrial myopathy with a typical onset before 20 years of age...

     (aka Ragged Red Fiber Myopathy)
  • RP combined with retardation, peripheral neuropathy, acanthotic (spiked) RBCs, ataxia, steatorrhea
    Steatorrhea
    Steatorrhea is the presence of excess fat in feces. Stools may also float due to excess lipid, have an oily appearance and be especially foul-smelling. An oily anal leakage or some level of fecal incontinence may occur. There is increased fat excretion, which can be measured by determining the...

    , is absence of VLDL is seen in abetalipoproteinemia
    Abetalipoproteinemia
    Abetalipoproteinemia, or Bassen-Kornzweig syndrome, is a rare autosomal recessive disorder that interferes with the normal absorption of fat and fat-soluble vitamins from food. It is caused by a deficiency of apolipoprotein B-48 and B-100, which are used in the synthesis and exportation of...

    .


Other conditions include neurosyphilis
Neurosyphilis
Neurosyphilis is an infection of the brain or spinal cord caused by the bacterium Treponema pallidum. It usually occurs in people who have had untreated syphilis for many years, usually about 10 - 20 years after first infection.-Symptoms and signs:...

, toxoplasmosis
Toxoplasmosis
Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. The parasite infects most genera of warm-blooded animals, including humans, but the primary host is the felid family. Animals are infected by eating infected meat, by ingestion of feces of a cat that has itself...

(Emedicine "Retinitis Pigmentosa") and Refsum's disease.

Genetics

Retinitis pigmentosa (RP) is one of the most common forms of inherited retinal degeneration
Degenerative disease
A degenerative disease, also called neurodegenerative disease, is a disease in which the function or structure of the affected tissues or organs will progressively deteriorate over time, whether due to normal bodily wear or lifestyle choices such as exercise or eating habits...

. This disorder is characterized by the progressive loss of photoreceptor cells and may eventually lead to blindness.

There are multiple genes
Gênes
Gênes is the name of a département of the First French Empire in present Italy, named after the city of Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa, and it was divided in the arrondissements of Genoa, Bobbio, Novi Ligure, Tortona and...

 that, when mutated, can cause the Retinitis pigmentosa phenotype
Phenotype
A phenotype is an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, behavior, and products of behavior...

. In 1989, a mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...

 of the gene for rhodopsin
Rhodopsin
Rhodopsin, also known as visual purple, is a biological pigment of the retina that is responsible for both the formation of the photoreceptor cells and the first events in the perception of light. Rhodopsins belong to the G-protein coupled receptor family and are extremely sensitive to light,...

, a pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 that plays an essential part in the visual transduction cascade
Visual phototransduction
Visual phototransduction is a process by which light is converted into electrical signals in the rod cells, cone cells and photosensitive ganglion cells of the retina of the eye....

 enabling vision in low-light conditions, was identified. Since then, more than 100 mutations have been found in this gene, accounting for 15% of all types of retinal degeneration
Retinopathy
Retinopathy is a general term that refers to some form of non-inflammatory damage to the retina of the eye. Frequently, retinopathy is an ocular manifestation of systemic disease.-Pathophysiology:Causes of retinopathy are varied:...

. Most of those mutations are missense mutation
Missense mutation
In genetics, a missense mutation is a point mutation in which a single nucleotide is changed, resulting in a codon that codes for a different amino acid . This can render the resulting protein nonfunctional...

s and inherited mostly in a dominant manner.

Types include:
|
| RP1
RP1
Oxygen-regulated protein 1 also known as retinitis pigmentosa 1 protein is a protein that in humans is encoded by the RP1 gene.- Function :...


| Retinitis pigmentosa-1> |
| RP2
| Retinitis pigmentosa-2> |
| RPGR
| Retinitis pigmentosa-3> |
| PRPH2
| Retinitis pigmentosa-7> |
| RP9
RP9
Retinitis pigmentosa 9 , also known as RP9 or PAP-1, is a protein which in humans is encoded by the RP9 gene.- Function :...


| Retinitis pigmentosa-9> |
| IMPDH1
IMPDH1
Inosine-5'-monophosphate dehydrogenase 1, also known as IMP dehydrogenase 1, is an enzyme that in humans is encoded by the IMPDH1 gene.- Function :...


| Retinitis pigmentosa-10> |
| PRPF31
PRPF31
PRP31 pre-mRNA processing factor 31 homolog , also known as PRPF31, is a protein which in humans is encoded by the PRPF31 gene.- Function :PRPF31 is the gene coding for the splicing factor hPRP31...


| Retinitis pigmentosa-11> |
| CRB1
CRB1
Crumbs homolog 1 is a protein that in humans is encoded by the CRB1 gene.This gene encodes a protein which is similar to the Drosophila crumbs protein and localizes to the inner segment of mammalian photoreceptors...


| Retinitis pigmentosa-12, autosomal recessive> |
| PRPF8
PRPF8
Pre-mRNA-processing-splicing factor 8 is a protein that in humans is encoded by the PRPF8 gene.-Interactions:PRPF8 has been shown to interact with WDR57 and EFTUD2.-External links:* -Further reading:...


| Retinitis pigmentosa-13> |
| TULP1
TULP1
Tubby-related protein 1 is a protein that in humans is encoded by the TULP1 gene.-Further reading:...


| Retinitis pigmentosa-14> |
| CA4
| Retinitis pigmentosa-17> |
| HPRP3
| Retinitis pigmentosa-18> |
| ABCA4
ABCA4
ATP-binding cassette, sub-family A , member 4, also known as ABCA4 or ABCR, is a protein which in humans is encoded by the ABCA4 gene....


| Retinitis pigmentosa-19> |
| EYS
Eys
Eys is a village in the municipality of Gulpen-Wittem, Limburg, the Netherlands. The town is located 3 km. from Gulpen and 17 km. from provincial capital Maastricht. Furthermore, it is characterised by its location in the hilly landscape of South Limburg. The village was first mentioned...


| Retinitis pigmentosa-25> |
| CERKL
| Retinitis pigmentosa-26> |
| FSCN2
FSCN2
Fascin-2 is a protein that in humans is encoded by the FSCN2 gene.-External links:*...


| Retinitis pigmentosa-30> |
| TOPORS
TOPORS
E3 ubiquitin-protein ligase Topors is an enzyme that in humans is encoded by the TOPORS gene.-Further reading:...


| Retinitis pigmentosa-31> |
| SNRNP200
| Retinitis pigmentosa 33> |
| SEMA4A
SEMA4A
Semaphorin-4A is a protein that in humans is encoded by the SEMA4A gene.-Further reading:...


| Retinitis pigmentosa-35> |
| PRCD
| Retinitis pigmentosa-36> |
| NR2E3
| Retinitis pigmentosa-37> |
| MERTK
MERTK
Proto-oncogene tyrosine-protein kinase MER is an enzyme that in humans is encoded by the MERTK gene.-External links:*...


| Retinitis pigmentosa-38> |
| USH2A
USH2A
Usherin is a protein that in humans is encoded by the USH2A gene.-External Links:* -Further reading:...


| Retinitis pigmentosa-39> |
| PROM1
| Retinitis pigmentosa-41> |
| KLHL7
KLHL7
Kelch-like protein 7 is a protein that in humans is encoded by the KLHL7 gene.-External links:*...


| Retinitis pigmentosa-42> |
| CNGB1
CNGB1
Cyclic nucleotide gated channel beta 1, also known as CNGB1, is a human gene encoding an ion channel protein.-External links:*...


| Retinitis pigmentosa-45> |
| BEST1
| Retinitis pigmentosa-50> |
| TTC8
TTC8
Tetratricopeptide repeat domain 8 also known as Bardet-Biedl syndrome 8 is a protein that in humans is encoded by the TTC8 gene.- Function :TTC8 is associated with gamma-tubulin, BBS4, and PCM1 in the centrosome...


| Retinitis pigmentosa 51> |
| C2orf71
| Retinitis pigmentosa 54> |
| ARL6
ARL6
ADP-ribosylation factor-like protein 6 is a protein that in humans is encoded by the ARL6 gene.-External Links:* -Further reading:...


| Retinitis pigmentosa 55> |
| ZNF513
| Retinitis pigmentosa 58> |
| BEST1
| Retinitis pigmentosa, concentric> |
| PRPH2
| Retinitis pigmentosa, digenic> |
| LRAT
| Retinitis pigmentosa, juvenile> |
| SPATA7
SPATA7
Spermatogenesis-associated protein 7 is a protein that in humans is encoded by the SPATA7 gene.-Further reading:...


| Retinitis pigmentosa, juvenile, autosomal recessive> |
| CRX
CRX (gene)
Cone-rod homeobox protein is a protein that in humans is encoded by the CRX gene.-External links:*...


| Retinitis pigmentosa, late-onset dominant> |
| RPGR
| Retinitis pigmentosa, X-linked, and sinorespiratory infections, with or without deafness>
OMIM Gene Type


The rhodopsin gene encodes
Coding strand
When referring to DNA transcription, the coding strand is the DNA strand which has the same base sequence as the RNA transcript produced...

 a principal protein of photoreceptor outer segments. Studies show that mutations in this gene are responsible for approximately 25% of autosomal dominant forms of RP.

Mutations in four pre-mRNA splicing factors are known to cause autosomal dominant retinitis pigmentosa. These are PRPF3
PRPF3
U4/U6 small nuclear ribonucleoprotein Prp3 is a protein that in humans is encoded by the PRPF3 gene.-External links:* -Further reading:...

, PRPF8
PRPF8
Pre-mRNA-processing-splicing factor 8 is a protein that in humans is encoded by the PRPF8 gene.-Interactions:PRPF8 has been shown to interact with WDR57 and EFTUD2.-External links:* -Further reading:...

, PRPF31
PRPF31
PRP31 pre-mRNA processing factor 31 homolog , also known as PRPF31, is a protein which in humans is encoded by the PRPF31 gene.- Function :PRPF31 is the gene coding for the splicing factor hPRP31...

 and PAP1
RP9
Retinitis pigmentosa 9 , also known as RP9 or PAP-1, is a protein which in humans is encoded by the RP9 gene.- Function :...

. These factors are ubiquitously expressed and it is still a puzzle as to why defects in a ubiquitous factor should only cause disease in the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...

.

Up to 150 mutations have been reported to date in the opsin
Opsin
Opsins are a group of light-sensitive 35–55 kDa membrane-bound G protein-coupled receptors of the retinylidene protein family found in photoreceptor cells of the retina. Five classical groups of opsins are involved in vision, mediating the conversion of a photon of light into an electrochemical...

 gene associated with the RP since the Pro23His mutation in the intradiscal domain of the protein was first reported in 1990. These mutations are found throughout the opsin gene and are distributed along the three domains of the protein (the intradiscal, transmembrane, and cytoplasmic domains
Protein domain
A protein domain is a part of protein sequence and structure that can evolve, function, and exist independently of the rest of the protein chain. Each domain forms a compact three-dimensional structure and often can be independently stable and folded. Many proteins consist of several structural...

). One of the main biochemical causes of RP in the case of rhodopsin mutations is protein misfolding
Protein folding
Protein folding is the process by which a protein structure assumes its functional shape or conformation. It is the physical process by which a polypeptide folds into its characteristic and functional three-dimensional structure from random coil....

, and molecular chaperones have also been involved in RP. It was found that the mutation of codon 23 in the rhodopsin gene, in which proline
Proline
Proline is an α-amino acid, one of the twenty DNA-encoded amino acids. Its codons are CCU, CCC, CCA, and CCG. It is not an essential amino acid, which means that the human body can synthesize it. It is unique among the 20 protein-forming amino acids in that the α-amino group is secondary...

 is changed to histidine
Histidine
Histidine Histidine, an essential amino acid, has a positively charged imidazole functional group. It is one of the 22 proteinogenic amino acids. Its codons are CAU and CAC. Histidine was first isolated by German physician Albrecht Kossel in 1896. Histidine is an essential amino acid in humans...

, accounts for the largest fraction of rhodopsin mutations in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. Several other studies have reported other mutations which also correlate with the disease. These mutations include Thr58Arg, Pro347Leu, Pro347Ser, as well as deletion of Ile-255.

In 2000, a rare mutation in codon 23 was reported causing autosomal dominant retinitis pigmentosa, in which proline changed to alanine
Alanine
Alanine is an α-amino acid with the chemical formula CH3CHCOOH. The L-isomer is one of the 20 amino acids encoded by the genetic code. Its codons are GCU, GCC, GCA, and GCG. It is classified as a nonpolar amino acid...

. However, this study showed that the retinal dystrophy
Retinopathy
Retinopathy is a general term that refers to some form of non-inflammatory damage to the retina of the eye. Frequently, retinopathy is an ocular manifestation of systemic disease.-Pathophysiology:Causes of retinopathy are varied:...

 associated with this mutation was characteristically mild in presentation and course. Furthermore, there was greater preservation in electroretinography
Electroretinography
Electroretinography measures the electrical responses of various cell types in the retina, including the photoreceptors , inner retinal cells , and the ganglion cells. Electrodes are usually placed on the cornea and the skin near the eye, although it is possible to record the ERG from skin electrodes...

 amplitude
Amplitude
Amplitude is the magnitude of change in the oscillating variable with each oscillation within an oscillating system. For example, sound waves in air are oscillations in atmospheric pressure and their amplitudes are proportional to the change in pressure during one oscillation...

s than the more prevalent Pro23His mutation.

Treatment

Currently there is no treatment for Retinitis Pigmentosa. The progression of the disease can be reduced by the daily intake of 15000 IU
International unit
In pharmacology, the International Unit is a unit of measurement for the amount of a substance, based on biological activity or effect. It is abbreviated as IU, as UI , or as IE...

 (equivalent to 4.5 mg) of vitamin A palmitate in some patients. Recent studies have shown that proper vitamin A
Vitamin A
Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...

 supplementation can postpone blindness by up to 10 years (by reducing the 10% loss pa to 8.3% pa) in some patients in certain stages of the disease.

Research on possible treatments

Future treatments may involve retinal transplant
Organ transplant
Organ transplantation is the moving of an organ from one body to another or from a donor site on the patient's own body, for the purpose of replacing the recipient's damaged or absent organ. The emerging field of regenerative medicine is allowing scientists and engineers to create organs to be...

s, artificial retinal implant
Retinal implant
A retinal implant is a biomedical implant technology currently being developed by a number of private companies and research institutions worldwide. The implant is meant to partially restore useful vision to people who have lost theirs due to degenerative eye conditions such as retinitis...

s, gene therapy
Gene therapy
Gene therapy is the insertion, alteration, or removal of genes within an individual's cells and biological tissues to treat disease. It is a technique for correcting defective genes that are responsible for disease development...

, stem cell
Stem cell
This article is about the cell type. For the medical therapy, see Stem Cell TreatmentsStem cells are biological cells found in all multicellular organisms, that can divide and differentiate into diverse specialized cell types and can self-renew to produce more stem cells...

s, nutritional supplements
Dietary supplement
A dietary supplement, also known as food supplement or nutritional supplement, is a preparation intended to supplement the diet and provide nutrients, such as vitamins, minerals, fiber, fatty acids, or amino acids, that may be missing or may not be consumed in sufficient quantities in a person's diet...

, and/or drug therapies
Pharmacology
Pharmacology is the branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function...

.

2006: Stem cells: UK Researchers working with mice, transplanted mouse stem cells which were at an advanced stage of development, and already programmed to develop into photoreceptor cells, into mice that had been genetically induced to mimic the human conditions of retinitis pigmentosa and age-related macular degeneration
Macular degeneration
Age-related macular degeneration is a medical condition which usually affects older adults and results in a loss of vision in the center of the visual field because of damage to the retina. It occurs in “dry” and “wet” forms. It is a major cause of blindness and visual impairment in older adults...

. These photoreceptors developed and made the necessary neural connections to the animal's retinal nerve cells, a key step in the restoration of sight. Previously it was believed that the mature retina has no regenerative
Regeneration (biology)
In biology, regeneration is the process of renewal, restoration, and growth that makes genomes, cells, organs, organisms, and ecosystems resilient to natural fluctuations or events that cause disturbance or damage. Every species is capable of regeneration, from bacteria to humans. At its most...

 ability. This research may in the future lead to using transplants in humans to relieve blindness.

2008: Scientists at the Osaka Bioscience Institute have identified a protein, named Pikachurin
Pikachurin
Pikachurin, also known as protein-like polysaccharide and EGF-like, fibronectin type-III and laminin G-like domain-containing polysaccharide , is a polysaccharide that in humans is encoded by the EGFLAM gene...

, which they believe could lead to a treatment for retinitis pigmentosa.

2010: A possible gene therapy
Gene therapy
Gene therapy is the insertion, alteration, or removal of genes within an individual's cells and biological tissues to treat disease. It is a technique for correcting defective genes that are responsible for disease development...

 seems to work in mice.

2010:R-Tech Ueno(Japanese Medicine manufacture enterprise )Completes Phase II Clinical Study on Ophthalmic Solution UF-021 (Product Name Ocuseva (TM)) on Retinitis Pigmentosa

Also see Wikipedia entry on TUDCA

Notable people with RP

  • Sue Arnold
    Sue Arnold
    Sue Arnold is a British journalist, who writes or has written for both The Observer and The Guardian.Since losing her sight as a result of a medical condition her writing has often been related to radio criticism and reviewing of audio books. Her mother was Burmese and her father British and she...

    , Anglo-Burmese UK based journalist
  • Richard H. Bernstein
    Richard H. Bernstein
    Richard H. Bernstein is an American lawyer, practicing at The Law Offices of Sam Bernstein. He also is an adjunct professor at the University of Michigan and served on the Wayne State University Board of Governors for one eight-year term, including two years as vice chair and two more as chair,...

    , lawyer, triathlon athlete, rights advocate for the visually impaired
  • Willie Brown
    Willie Brown (politician)
    Willie Lewis Brown, Jr. is an American politician of the Democratic Party. He served over 30 years in the California State Assembly, spending 15 years as its Speaker, and afterward served as the 41st mayor of San Francisco, the first African American to do so...

    , former Mayor of San Francisco
  • Viviane Forest
    Viviane Forest
    Viviane Forest is a multi-sport Paralympic medallist. She was born and raised in Quebec, and currently resides in Edmonton.-Sporting career:Forest played on Canada's gold medal-winning goalball teams in Sydney and Athens....

    , Canadian Paralympic alpine skier
  • Gordon Gund
    Gordon Gund
    Gordon Gund is an United States businessman and professional sports owner. He is the CEO of Gund Investment Corporation. He is the former co-owner of the San Jose Sharks and former principal owner of the Cleveland Cavaliers and is currently a minority owner of the Cavaliers...

    , U.S. sports team owner
  • Sheena Iyengar
    Sheena Iyengar
    Sheena Iyengar is the inaugural S.T. Lee Professor of Business in the Management Division at Columbia Business School and the Research Director at the Jerome A. Chazen Institute of International Business. She is known for her research on choice....

    , management guru
  • Ryan Knighton
    Ryan Knighton
    Ryan Knighton is a Canadian writer best known for being a blind author of books dealing with life and living life with blindness, such as Cockeyed: A Memoir and C'mon Papa - Dispatches from a dad in the dark. He teaches English and creative writing at a university and lives in Vancouver with his...

    , Canadian writer
  • Jim Knipfel
    Jim Knipfel
    Jim Knipfel , is an American novelist, autobiographer, and journalist.A native of Wisconsin, Knipfel, who suffers from retinitis pigmentosa, is the author of a series of critically acclaimed memoirs, Slackjaw, Quitting the Nairobi Trio, and Ruining It for Everybody, as well as two novels, The...

    , American novelist, autobiographer, and journalist
  • Amar Latif
    Amar Latif
    Amar Latif is a blind British entrepreneur, actor, director, motivational speaker and world traveller. His blindness is due to the incurable eye condition Retinitis Pigmentosa...

     Scottish entrepreneur, television actor, director and motivational speaker
  • Isaac Lidsky
    Isaac Lidsky
    Isaac Lidsky is a lawyer and former child actor. As a law clerk for Justices Sandra Day O'Connor and Ruth Bader Ginsburg in 2008-09, he became the first blind US Supreme Court clerk....

    , former child actor and first blind US Supreme Court clerk
  • Tony Sarre
    Tony Sarre
    -Early life:Tony Sarre, is an Australian filmmaker who, at age 16, was told that retinitis pigmentosa, a degenerative eye disease, would send him blind in a year...

    , filmmaker
  • Woody Shaw
    Woody Shaw
    Woody Shaw was an American jazz trumpeter, flugelhornist, cornetist, composer and band leader, often referred to as the "last innovator" in the jazz trumpet lineage...

    , American jazz musician
  • Amanda Swafford
    Amanda Swafford
    Amanda Lynn Swafford is an American fashion model and television personality. She came in third place on Cycle 3 of the reality television show America's Next Top Model. Swafford is legally blind; she is afflicted with retinitis pigmentosa, a degenerative eye condition...

    , American model and America's Next Top Model
    America's Next Top Model
    America's Next Top Model is a reality television show in which a number of women compete for the title of America's Next Top Model and a chance to start their career in the modeling industry....

    contestant
  • John Totleben
    John Totleben
    John Totleben is an American illustrator working mostly in comics.-Biography:After studying art at a vocational high school in Erie, Totleben attended The Kubert School for one year...

    , American illustrator
  • Rigo Tovar
    Rigo Tovar
    Rigoberto Tovar García was a Mexican singer best known as Rigo Tovar. Famous for his cumbia songs, Tovar is considered a musical pioneer by fusing electric guitar, synthesizer, and rock melodies with traditional Mexican music.Tovar was born and raised in Matamoros, Tamaulipas, Mexico...

    , Mexican singer, composer, songwriter
  • Mildred Weisenfeld
    Mildred Weisenfeld
    Mildred Mosler Weisenfeld is the Brooklyn-born founder of national not-for-profit foundation the National Council to Combat Blindness in 1946, now known as Fight for Sight, an organization based in New York City that provides initial funds to promising scientists early in their careers...

    , founder of the Fight for Sight
    Fight for Sight (U.S.)
    Fight for Sight is a nonprofit organization in the United States which funds medical research in vision and ophthalmology. It was formed in 1946 as the National Council to Combat Blindness , the first non-profit in the United States to fund vision research; 2011 marked its 65th anniversary.Based in...

     eye research foundation in 1946.
  • Jon Wellner
    Jon Wellner
    Jon Wellner is an American actor, best known for his role as Henry Andrews on CSI: Crime Scene Investigation.-Filmography:Jon Wellner is an American actor, best known for his role as Henry Andrews on CSI: Crime Scene Investigation....

    , actor
  • Steve Wynn, Las Vegas casino developer

See also

  • Cone dystrophy
    Cone dystrophy
    A cone dystrophy is an inherited ocular disorder characterized by the loss of cone cells, the photoreceptors responsible for both central and color vision....

  • Visual prosthetic
  • List of eye diseases and disorders
  • Progressive retinal atrophy
    Progressive retinal atrophy
    Progressive retinal atrophy is a group of genetic diseases seen in certain breeds of dogs and, more rarely, cats. Similar to retinitis pigmentosa in humans, it is characterized by the bilateral degeneration of the retina, causing progressive vision loss culminating in blindness...

     for the condition in dogs
  • Retinal Degeneration (Rhodopsin Mutation)
    Retinal Degeneration (Rhodopsin Mutation)
    Retinal degeneration is the deterioration of the retina caused by the progressive and eventual death of the cells of the retina. There are several reasons for retinal degeneration, including artery or vein occlusion, diabetic retinopathy, R.L.F./R.O.P...

  • Adeno associated virus and gene therapy of the human retina
    Adeno associated virus and gene therapy of the human retina
    Gene therapy is the use of genetic material inserted into a patient’s cell for the treatment of an inherited or acquired diseases. There are many medical conditions that are a result of mutation in patient’s gene...


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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