Albinism (achromia, achromasia, achromatosis) is defined as a group of inherited disorders characterized by a deficit in the production of melanin with deficiency or absence of pigment in the skin, hair and eyes.
The main sign of albinism is the lack of pigment in skin, eyes, and hair. Other symptoms include vision difficulties. Common signs and symptoms are :
- Pink skin. However, skin color can vary from white to a brown and may even be seen as a normal hue. Skin can also change in children and teens as melanin production increases during the teenage years.
- The appearance of freckles or moles on exposed skin.
- White hair. Patients of Asian or African descent might present yellow, red, or brown hair that may darken over the years.
- Light blue to brown eyes and translucent irises.
- Nystagmus, photophobia, astigmatism, strabismus, or extreme farsightedness or nearsightedness can be seen.
Jaw & Teeth
In addition to improved uncorrected and corrected distance visual acuity and significant reduction of refractive error, all patients had a marked reduction of glare and photophobia after surgery. [ncbi.nlm.nih.gov]
At age 2 months, nystagmus and esotropia prompted ophthalmic evaluation. The appearance of choroidal sclerosis and atrophic retinal patches led to further evaluation at age 8 years. [ncbi.nlm.nih.gov]
In the case of esotropia or “crossed eyes,” surgery may help vision by expanding the visual field (the area that the eyes can see while looking at one point). Surgical intervention is also available to minimize nystagmus. [albinism.org]
In the case of esotropia or "crossed eyes," surgery may help vision by expanding the visual field, that is, the area that the eyes can see while looking a one point. Tints and sunglasses can help with light sensitivity. [verslo.is]
Strabismus: Misaligned eyes or disconjugate gaze due to misrouted optic nerve fibers at the chiasm, for example, exotropia, esotropia, vertical misalignment Reduced stereopsis (fine depth perception) and binocular vision due to strabismus Reduced iris [statpearls.com]
Face, Head & Neck
After a physical examination coupled with a description of pigmentation changes, and familial comparisons, albinism can usually be diagnosed . The physical exam will also be paired with an eye exam. A genetic test is necessary in order to confirm albinism and detect which specific subtype of the condition is present.
There is no cure for albinism, only management measures that a patient is recommended to follow . A patient experiencing vision problems may be prescribed glasses, bifocals, or other vision aids. If a patient is experiencing strabismus, eye patches, especially for infants, or surgery might be beneficial. Tinted glasses may be used to improve photophobia.
Other recommendations concern the protection of the patient’s sensitive skin. Wearing a hat while in the sun, using sunblock on exposed skin, or wearing long sleeves and pants is recommended.
While albinism has no effect on a patient’s lifespan, it can limit their activities. Due to the sensitive nature of the skin, daily activities in normal sunlight might prove to be difficult without some layer of protection. Sunlight or other bright lights might affect vision due to the eyes’ sensitivity.
- The cause of albinism type OCA 1 and AROA, lies in a defective enzyme called tyrosinase. This enzyme contains copper and is involved in the production of melanin and other pigments from tyrosine by oxidation . The tyrosinase enzyme is encoded by the TYR gene with the gene location 11q14-21.
- Mutations in tyrosinase-related protein 1 (TRP1), coded on chromosome 9 cause OCA 3.
- Mutation to the P gene, enconding for P protein which plays a role in regulating the pH of melanosomes, causes OCA 2.
Albinism can affect people from all ethnic backgrounds. According to reports, it occurs in about one person out of 17,000 people worldwide. A patient’s lifespan is not affected by albinism as there is no link between the condition and mortality . In general, a person’s health will remain normal aside from the associated conditions.
A congenital hypopigmentation within the systemic and ocular tissues is present . Cellular pigmentation relies on the individual cell’s capability to manufacture as well as isolate the melanin pigment. This process happens inside organelles known as melanosomes. These are found in the melanocyte cells of the iris’s stroma, the ciliary body, choroid pigments, the skin, the conjunctive of the eye, and the hair. Melanin is synthesised through tyrosine inside of the melanosome.
Tyrosinase plays a dominant role in albinism and affected individuals are therefore classified as being tyrosinase-positive or tyrosinase-negative depending on the results of a hair bulb test or an electron microscopy of the skin or hair. In both cases, there is usually an autosomal recessive inheritance pattern detected. If a patient is found to be tyrosinase-negative, the enzyme is considered to be inactive. This stops the cell from using the enzyme in order to produce melanin pigment. In the opposite case, the activity level of the tyrosinase enzyme is actually normal, but the cell is unable to synthesize the melanin due to defects in other enzymes involved in the pathway.
Albinism is a group of inherited disorders characterized by a deficit in the production of melanin with deficiency or absence of pigment. The disorder is also known as achromia, achromatosis, or achromasia . The condition is classified in two forms, ocular albinism (OA) and oculocutaneous albinism (OCA), which are divided into several subtypes based on the location of the genetic mutation, (OCA 1, OCA 2, OCA 3) and (OA1, AROA).
Along with the loss of pigment, the condition can also be associated with vision problems including nystagmus, astigmatism, and photophobia. In relation to the skin, albinism is associated with various skin cancers and chronic sunburns.
Albinism is an inherited condition distinguishable by the absence of melanin pigment in the patient. This pigment is responsible for the color of a person’s hair, eyes, and skin. The condition is usually accompanied by a sensitivity to the sun and is linked to an increased risk of various skin problems including skin cancer. Vision problems are also associated with albinism.
Albinism can affect people from all ethnic background. It is genetic and can’t be caused by outside influences.
There is no cure for albinism, but there are a number of things that a person can do to manage the condition. Using protective layers including sunscreen and loose clothes is recommended to protect sensitive skin. Eyeglasses can be prescribed for vision problems and sunglasses are recommended when outdoors.
Some people may also experience nonmedical issues due to their albinism. This can include social isolation and discrimination. These issues can be handled with the help of a therapist or other counsellor who can help a patient work through these social problems.
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