Albinism is a rare group of genetic disorders that cause the skin, hair, or eyes to have little or no color. Albinism is also associated with vision problems. According to the National Organization for Albinism and Hypopigmentation (NOAH), approximately one in 17,000 people have a form of albinism. (NOAH)
Albinism is caused by a defect in one of several genes that produce or distribute melanin (natural pigment). The defect may result in the absence of melanin production, or a reduced amount of melanin production. Albinism is inherited and requires the defective gene to be passed down by both parents.
There are numerous types of albinism, which are identified by different gene defects. The types of albinism include:
Oculocutaneous Albinism (OCA)
OCA affects the skin, hair, and eyes. There are several subtypes of OCA, which include:
OCA1 is caused by a defect in the tyrosinase enzyme. There are two subtypes of OCA1.
People with OCA1a have a complete absence of melanin. They have white hair, very pale skin, and light eyes.
People with OCA1b produce some melanin. They have light-colored skin, hair, and eyes. Their coloring may increase as they age.
OCA2 is less severe than OCA1. It is caused by a defect in the OCA2 gene that results in reduced melanin production. People with OCA2 are born with slight coloring and have light skin, and their hair may be yellow, blond, or light brown. Common in Sub-Saharan Africans, African Americans and Native Americans.
OCA3 is a defect in the TYRP1 gene, and it usually affects dark-skinned people, particularly in black South Africans. People with OCA3 have reddish-brown skin, reddish hair, and hazel or brown eyes.
OCA4 is caused by a defect in the SLC45A2 protein that results in the minimal production of melanin, commonly found in people of East Asian descent. People with type OCA4 have similar symptoms as people with OCA2.
Ocular Albinism (OA)
OA is caused by a gene mutation on the X chromosome and occurs almost exclusively in males. This type of albinism only affects the eyes. People with OA have normal hair, skin, and eye coloring, but have no coloring in the retina (the back of the eye).
Hermansky-Pudlak Syndrome (HPS)
HPS is a rare form of albinism that is caused by a defect in one of eight genes. It produces symptoms similar to OCA, and occurs with lung, bowel, and bleeding disorders.
Chediak-Higashi syndrome is another rare form of albinism that is caused by a defect in the LYST gene. It produces symptoms similar to OCA, but may not affect all areas of the skin. The hair is usually brown or blond with a silvery sheen, and the skin is usually creamy white to grayish. People with Chediak-Higashi syndrome have a defect in the white blood cells, increasing their risk of infections.
Griscelli Syndrome (GS)
GS is an extremely rare genetic disorder that is caused by a defect in one of three genes. There only have been 60 known cases of GS worldwide since 1978. GS is characterized by albinism (may not affect the entire body), immune problems, and neurological problems. GS usually results in death within the first decade of life.
Albinism is an inherited disorder that is present at birth. Children are at risk of being born with albinism if they have parents with albinism, or parents who carry the gene for albinism.
People with albinism will have the following symptoms:
- an absence of color in the hair, skin, or eyes
- lighter than normal coloring of the hair, skin, or eyes
- patches of skin that have an absence of color
Albinism is associated with vision problems, which may include:
- strabismus (crossed eyes)
- photophobia (sensitivity to light)
- nystagmus (involuntary rapid eye movements)
- impaired vision or blindness
The most accurate way to diagnose albinism is through genetic testing to detect defective genes related to albinism. Less accurate ways of detecting albinism include an evaluation of symptoms by your doctor, or an electroretinogram test (that measures the response of the light-sensitive cells in the eyes) to reveal problems with your eyes associated with albinism.
There is no cure for albinism. Treatment for albinism is provided to relieve symptoms and to prevent sun damage. Treatment for albinism may include:
- sunglasses to protect the eyes from UV rays
- protective clothing and sunscreen to protect the skin from UV rays
- prescription eyeglasses to correct vision problems
- surgery on the muscles of the eyes to correct abnormal eye movements
Most forms of albinism do not affect lifespan. Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, and Griscelli syndrome, however, do affect lifespan because of the co-occurring health problems associated with the syndromes. People with albinism may have to limit their outdoor activities because their skin and eyes are sensitive to the sun. UV rays from the sun can cause skin cancer and vision loss in some people with albinism.