Albinism
Albinism
(Hypopigmentation; Oculocutaneous Albinism; Ocular Albinism)
Definition
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Oculocutaneous albinism
- Type 1—complete absence of pigment. Skin, hair, and eyes lack all pigment from birth. Freckles or moles will not appear at any time during their lifetimes. This group is divided into several subtypes depending on associated characteristics.
- Type 2—decreased pigment, but may still have freckles and moles. This form of albinism is more common among persons of African descent. This form may be associated with such minor pigment loss that it is noticed only by looking at differences among other non-affected family members.
- Both Type 1 and Type 2 albinism are usually associated with visual problems including nystagmus (abnormal jumping movements of the eyes) and decreased visual acuity, which is frequently not fully improved with glasses or contact lenses.
- Type 3—reddish brown skin, reddish hair, and hazel or brown eyes, generally black South Africans.
- Type 4––similar to type 2, predominantly in Japanese persons.
- Ocular albinism––an X-linked albinism where there are vision problems without changes in skin or hair.
- Hermansky-Pudlak––in addition to albinism, persons also have lung, bowel, and bleeding problems.
- Chediak-Higashi––in addition to albinism, persons also have immune problems with defects in the immune system.
Causes
Risk Factors
- Children of parents who have albinism
- Children of parents who do not have albinism, but carry the altered genes that cause this disorder
- A positive family history for albinism in a sibling or other relative
Symptoms
| Eye Symptom—Strabismus |
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Eye problems, such as:
- Strabismus or crossed or wandering eye
- Poor vision (which usually cannot be fully corrected with glasses or contacts)
- In some cases, functional blindness
- Nystagmus or irregular, rapid eye movement.
- Amblyopia or “lazy” eye.
- Photophobia–sensitivity to bright lights or glare
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Skin problems, including:
- Little or no pigmentation (resulting in extremely light or white skin)
- Extreme sensitivity to sunburn
- Very high susceptibility to skin cancer
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Hair problems, including:
- White hair
- Lighter than expected hair (often the forelock) being white
- Certain rare types of albinism, such as Hermansky-Pudlak syndrome, can cause other symptoms.
Diagnosis
Prognosis
- People with the most common forms of Type 1 and Type 2 albinism and ocular albinism have a normal lifespan.
- An increased risk of skin cancer exists. With careful monitoring, this risk can be reduced. Since melanoma skin cancer may occur, it is important to have frequent skin exams by a dermatologist (skin specialist).
- Affected people usually have unaffected children unless married to another individual with albinism.
- Albinism does not cause a delay in development or intellectual disability.
Treatment
Preventive Treatment
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Protect the skin:
- Sunburn and skin cancer risks can be reduced by avoiding the sun as much as possible
- Wear sunscreen with high SPF 30 or higher with UVA and UVB protection
- Cover as much skin as possible with clothing when exposed to the sun
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Protect the eyes:
- Wear sunglasses with UV protection whenever exposed to the sun
- Sunglasses (UV protected) may relieve photophobia
Specific Treatment of Symptoms
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For eyes:
- Glasses, contacts, and/or optical aids to help improve vision
- Surgery to correct certain eye problems, including crossed eyes or “lazy” eye
- Visual aids (in the classroom) to help children with albinism
- For skin: Surgery to treat and/or remove skin cancer , if necessary
Prevention
RESOURCES
Genetics Home Reference http://www.ghr.nlm.nih.gov
National Organization for Albinism and Hypopigmentation (NOAH) http://www.albinism.org
CANADIAN RESOURCES
Canadian Dermatology Association http://www.dermatology.ca
Canadian Ophthalmological Society http://www.eyesite.ca
References
Hong ES, Zeeb H, Repacholi MH. Albinism in Africa as a public health issue. BMC Public Health . 2006 Aug 17;6:212.
Perry PK, Silverberg NB. Cutaneous malignancy in albinism. Cutis . 2001 May;67(5):427-30.
Rees JL. Genetics of hair and skin color. Annu Rev Genet . 2003;37:67-90.
Surace EM, Domenici L, Cortese K, Cotugno G, Di Vicino U, Venturi C, et al. Amelioration of both functional and morphological abnormalities in the retina of a mouse model of ocular albinism following AAV-mediated gene transfer. Mol Ther . 2005 Oct;12(4):652-8.