The severity and prognosis vary with the type of mutation involved.

Retinitis pigmentosa is the leading cause of inherited blindness, with approximately 1/4,000 individuals experiencing the non-syndromic form of their disease within their lifetime. It is estimated that 1.5 million people worldwide are currently affected. Early onset RP occurs within the first few years of life and is typically associated with syndromic disease forms, while late onset RP emerges from early to mid-adulthood.

Autosomal dominant and recessive forms of retinitis pigmentosa affect both male and female populations equally; however, the less frequent X-linked form of the disease affects male recipients of the X-linked mutation, while females usually remain unaffected carriers of the RP trait. The X-linked forms of the disease are considered severe, and typically lead to complete blindness during later stages. In rare occasions, a dominant form of the X-linked gene mutation will affect both males and females equally.

Due to the genetic inheritance patterns of RP, many isolate populations exhibit higher disease frequencies or increased prevalence of a specific RP mutation. Pre-existing or emerging mutations that contribute to rod photoreceptor degeneration in retinitis pigmentosa are passed down through familial lines; thus, allowing certain RP cases to be concentrated to specific geographical regions with an ancestral history of the disease. Several hereditary studies have been performed to determine the varying prevalence rates in Maine (USA), Birmingham (England), Switzerland (affects 1/7000), Denmark (affects 1/2500), and Norway. Navajo Indians display an elevated rate of RP inheritance as well, which is estimated as affecting 1 in 1878 individuals. Despite the increased frequency of RP within specific familial lines, the disease is considered non-discriminatory and tends to equally affect all world populations.

RP may be:

(1) Non-syndromic, that is, it occurs alone, without any other clinical findings,

(2) Syndromic, with other neurosensory disorders, developmental abnormalities, or complex clinical findings, or

(3) Secondary to other systemic diseases.

- RP combined with deafness (congenital or progressive) is called Usher syndrome.

- Alport's syndrome is associated with RP and an abnormal glomerular-basement membrane leading nephrotic syndrome and inherited as X-linked dominant.

- RP combined with ophthalmoplegia, dysphagia, ataxia, and cardiac conduction defects is seen in the mitochondrial DNA disorder Kearns-Sayre syndrome (also known as Ragged Red Fiber Myopathy)

- RP combined with retardation, peripheral neuropathy, acanthotic (spiked) RBCs, ataxia, steatorrhea, is absence of VLDL is seen in abetalipoproteinemia.

- RP is seen clinically in association with several other rare genetic disorders (including muscular dystrophy and chronic granulomatous disease) as part of McLeod syndrome. This is an X-linked recessive phenotype characterized by a complete absence of XK cell surface proteins, and therefore markedly reduced expression of all Kell red blood cell antigens. For transfusion purposes these patients are considered completely incompatible with all normal and K0/K0 donors.

- RP associated with hypogonadism, and developmental delay with an autosomal recessive inheritance pattern is seen with Bardet-Biedl syndrome

Other conditions include neurosyphilis, toxoplasmosis and Refsum's disease.

Several mutations have been implicated as a cause of Oguchi disease. These include mutations in the arrestin gene or the rhodopsin kinase gene.

The condition is more frequent in individuals of Japanese ethnicity.

Choroideremia (; CHM) is a rare, X-linked recessive form of hereditary retinal degeneration that affects roughly 1 in 50,000 males. The disease causes a gradual loss of vision, starting with childhood night blindness, followed by peripheral vision loss, and progressing to loss of central vision later in life. Progression continues throughout the individual's life, but both the rate of change and the degree of visual loss are variable among those affected, even within the same family.

Choroideremia is caused by a loss-of-function mutation in the "CHM" gene which encodes Rab escort protein 1 (REP1), a protein involved in lipid modification of Rab proteins. While the complete mechanism of disease is not fully understood, the lack of a functional protein in the retina results in cell death and the gradual deterioration of the choroid, retinal pigment epithelium (RPE), and retinal photoreceptor cells.

As of 2017, there is no treatment for choroideremia; however, retinal gene therapy clinical trials have demonstrated a possible treatment.

The incidence and prevalence of PMD are unknown, and no studies have yet investigated its prevalence or incidence. However, it is generally agreed that PMD is a very rare condition. Some uncertainty regarding the incidence of PMD may be attributed to its confusion with keratoconus. PMD is not linked to race or age, although most cases present early in life, between 20 and 40 years of age. While PMD is usually considered to affect men and women equally, some studies suggest that it may affect men more frequently.

Several diseases have been observed in patients with PMD. However, no causal relationships have been established between any of the associated diseases and the pathogenesis of PMD. Such diseases include: chronic open-angle glaucoma, retinitis pigmentosa, retinal lattice degeneration, scleroderma, kerato-conjunctivitis, eczema, and hyperthyroidism.

While choroideremia is an ideal candidate for gene therapy there are other potential therapies that could restore vision after it has been lost later in life. Foremost of these is stem cell therapy. A clinical trial published in 2014 found that a subretinal injection of human embryonic stem cells in patients with age-related macular degeneration and Stargardt disease was safe and improved vision in most patients. Out of 18 patients, vision improved in 10, improved or remained the same in 7, and decreased in 1 patient, while no improvement was seen in the untreated eyes. The study found "no evidence of adverse proliferation, rejection, or serious ocular or systemic safety issues related to the transplanted tissue." A 2015 study used CRISPR/Cas9 to repair mutations in patient-derived induced pluripotent stem cells that cause X-linked retinitis pigmentosa. This study suggests that a patient's own repaired cells could be used for therapy, reducing the risk of immune rejection and ethical issues that come with the use of embryonic stem cells.

DUSN may be caused by a helminthic infection with Toxocara canis, Baylisascaris procyonis, or Ancylostoma caninum. The characteristic lesions are believed to result from a single nematode migrating within the subretinal space. Although previously thought to be endemic in some areas, that belief was likely due to under awareness. DUSN has been diagnosed in patients in many countries and climates including America, Brazil, China and India.

Kearns–Sayre syndrome occurs spontaneously in the majority of cases. In some cases it has been shown to be inherited through mitochondrial, autosomal dominant, or autosomal recessive inheritance. There is no predilection for race or sex, and there are no known risk factors. As of 1992 there were only 226 cases reported in published literature.

Retinitis is a genotypic disease which entails severe phenotypic representation. Types of Retinitis are currently considered the most complex forms of retinal disease. Such complexity in disease and incurability results from its complex mechanism. Retinitis is controlled by a single gene which can be inherited via an autosomal dominant, autosomal recessive, or X-linked gene. In many cases, individuals with Retinitis have parents and/or relatives who are unaffected by this disease.

There are two types of retinitis: Retinitis pigmentosa (RP) and cytomegalovirus (CMV) retinitis. Both conditions result in the swelling and damage to the retinitis. However, the key difference in both these conditions is that Retinitis pigmentosa is a genetic eye disease that you inherit from one or both of your parents. On the other hand, CMV retinitis develops from a viral infection in the retina. Although there is no cure for this disease, there are steps you can take to protect your eyes from worsening. Supplements can slow the progression of the disease and alleviate symptoms temporarily. Research also shows that vitamin A, lutein, and omega-3 fatty acids also help alleviate symptoms.

Revesz syndrome has so far been observed only in children. There is not much information about the disease because of its low frequency in general population and under reporting of cases.

Oguchi disease, also called congenital stationary night blindness, Oguchi type 1 or Oguchi disease 1, is an autosomal recessive form of congenital stationary night blindness associated with fundus discoloration and abnormally slow dark adaptation.

NARP syndrome is not curable. Symptomatic relief is targeted. Antioxidants play a role in improving the oxidative phosphorylation that is otherwise impaired.

Affected males develop generalized reticular hyper pigmentation in early childhood.

Hair often looks bedraggled or brushed backwards, hanging low on the forehead.

Among the associated extracutaneous manifestations are described:

- Respiratory infections

- Dyskeratosis corneal photophobia

- Hypohidrosis with large deficit of thermoregulation

- Growth retardation

- Gastrointestinal disorders

- Kidney disease

- Kidney stones

- Urinary infections

- Webbed feet or hands

- Electrolyte imbalance

- Retinitis pigmentosa

- Lymphoedema

- Thyroid abnormalities

Each patient shows some of the symptoms listed above. Not every sick person will show all of the listed symptoms.

In females the disease is characterized by skin rashes linear hyper pigmentation following the Blaschko's lines, morphologically similar to stage 3 pigment incontinence. There are no systemic manifestations associated with XLPDR in females.

One cause of the White Dot Syndromes as suggested by Gass involves viral or infectious agents. Specifically pertaining to the ‘AZOOR complex,’ Gass has postulated that a virus may enter the retina at the optic head and the infection may spread from one photoreceptor to another. Some unexplained features include the development of more than one disease in the same patient and the majority of cases occurring in females.

According to Becker’s common genetic hypothesis, “unlike mendelian genetic disorders, common autoimmune and inflammatory diseases arise from combinatorial interactions of common non-disease specific loci, disease specific loci, and specific environmental triggers.” An important aspect of this hypothesis pertains to the existence of common non-disease genes that predispose patients to autoimmune diseases. Jampol and Becker insinuate that ‘common susceptibility genes’ are present in patients affected by white dot syndromes. The presence of environmental triggers, such as viral infections, immunizations, and stress, and interactions with other genes contribute to the development of the white dot syndromes. Additionally, Jampol and Becker hypothesize that the predisposing genetic loci can be identified.

Gass points to a lack of evidence in support of the Becker theory. Instead, Gass highlights that although evidence indicates that patients with AZOOR have a greater chance of developing autoimmune diseases, this does not mean that the AZOOR complex of disorders are themselves autoimmune diseases. This is supported by the difficulty in detecting “retinal autoantibodies” in AZOOR patients.

Two other diseases which also present with white dots on the fundus are retinitis punctata albescens and fundus albipunctatus. These diseases are not white dot syndromes, but have much more defined etiology. Retinitis punctata albescens is caused by mutations in RLBP1, the gene for retinaldehyde binding protein 1. In comparison, fundus albipunctatus is caused by mutations in RDH5 gene for an 11-cis-RDH in RPE cells.

This condition is linked to the X chromosome.

- Siberian Husky - Night blindness by two to four years old.

- Samoyed - More severe disease than the Husky.

X-linked reticulate pigmentary disorder (also known as "familial cutaneous amyloidosis", "Partington amyloidosis", "Partington cutaneous amyloidosis", "Partington syndrome type II", "reticulate pigmentary disorder", and "X-linked reticulate pigmentary disorder with systemic manifestations") is a cutaneous condition that has been described in adult women that had linear streaks of hyperpigmentation and in which male patients manifested a reticulated mottled brown pigmentation of the skin, which, on biopsy, demonstrated dermal deposits of amyloid.

The syndrome is also referred with the acronym X-Linked-PDR or even XLPRD.It's a very rare disease, genetically determined, with a chronic course.

It was characterized in 1981. Mutation of the "POLA1" gene leads to loss of expression of the catalytic subunit of DNA polymerase-α and is responsible for XLPDR. Loss of POLA1 expression results in reduced levels of RNA:DNA hybrids in the cytosol and unexpectedly triggers aberrant immune responses (e.g. type I interferon production) which at least in part can account for the symptoms associated with XLPDR.

Currently, purine replacement via S-adenosylmethionine (SAM) supplementation in people with Arts syndrome appears to improve their condition. This suggests that SAM supplementation can alleviate symptoms of PRPS1 deficient patients by replacing purine nucleotides and open new avenues of therapeutic intervention. Other non-clinical treatment options include educational programs tailored to their individual needs. Sensorineural hearing loss has been treated with cochlear implantation with good results. Ataxia and visual impairment from optic atrophy are treated in a routine manner. Routine immunizations against common childhood infections and annual influenza immunization can also help prevent any secondary infections from occurring.

Regular neuropsychological, audiologic, and ophthalmologic examinations are also recommended.

Carrier testing for at-risk relatives and prenatal testing for pregnancies at increased risk are possible if the disease-causing mutation in the family is known.

Cytomegalovirus (a type of herpes virus) is what causes cytomegalovirus retinitis. Other types of herpes viruses include herpes simplex viruses and Epstein-Barr virus. Once an individual is infected with these viruses they stay in the body for life. What triggers the virus to reactivate are the following (though CMV can also be congenital).

- Leukemia

- AIDS

- Immunosuppressive chemotherapy

Commonly affected breeds:

- Akita - Symptoms at one to three years old and blindness at three to five years old. Selective breeding has greatly reduced the incidence of this disease in this breed.

- Miniature longhaired Dachshund - Symptoms at six months old.

- Papillon - Slowly progressive with blindness at seven to eight years old.

- Tibetan Spaniel - Symptoms at three to five years old.

- Tibetan Terrier - PRA3/RCD4 disease of middle age dogs. http://www.ttca-online.org/html/Petersen-Jones_PRA_article.pdf

- Samoyed - Symptoms by three to five years old.

Diffuse unilateral subacute neuroretinitis (DUSN) is a rare condition that occurs in otherwise healthy, often young patients and is due to the presence of a subretinal nematode.

One family of 68 individuals over 5 generations was studied and the prevalence of disease among the family members suggests that it is indicative of dominant inheritance that is not sexually linked. This is supported by the fact that the disease failed to skip generations even in the absence of intermarriages and that disease incidence was independent of sex. The current findings suggest that the cause of the disease could be narrowed down to one enzymatic defect that is involved in the development of neuroectodermal tissue, however the exact molecular mechanisms are currently unknown. The other symptoms that arise such as bone defects and diabetes may be secondary to this enzymatic defect.

White dot syndromes are inflammatory diseases characterized by the presence of white dots on the fundus, the interior surface of the eye. The majority of individuals affected with white dot syndromes are younger than fifty years of age. Some symptoms include blurred vision and visual field loss. There are many theories for the etiology of white dot syndromes including infectious, viral, genetics and autoimmune.

Classically recognized white dot syndromes include:

- Acute posterior multifocal placoid pigment epitheliopathy (APMPPE)

- Birdshot chorioretinopathy

- Multiple evanescent white dot syndrome (MEWDS)

- Acute zonal occult outer retinopathy (AZOOR)

- Multifocal choroiditis and panuveitis (MCP)

- Punctate inner choroiditis (PIC)

- Serpiginous choroiditis

The clinical course of BVVL can vary from one patient to another. There have been cases with progressive deterioration, deterioration followed by periods of stabilization, and deterioration with abrupt periods of increasing severity.

The syndrome has previously been considered to have a high mortality rate but the initial response of most patients to the Riboflavin protocol are very encouraging and seem to indicate a significantly improved life expectancy could be achievable. There are three documented cases of BVVL where the patient died within the first five years of the disease. On the contrary, most patients have survived more than 10 years after the onset of their first symptom, and several cases have survived 20–30 years after the onset of their first symptom.

Families with multiple cases of BVVL and, more generally, multiple cases of infantile progressive bulbar palsy can show variability in age of disease onset and survival. Dipti and Childs described such a situation in which a family had five children that had Infantile PBP. In this family, three siblings showed sensorineural deafness and other symptoms of BVVL at an older age. The other two siblings showed symptoms of Fazio-Londe disease and died before the age of two.