Understanding Albinism

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6 Jul 2024
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Understanding Albinism


Medically reviewed by Susan Bard, MD — Written by Rose Kivi and Matthew Solan — Updated on April 19, 2023

Albinism is a rare genetic condition that causes the lack of pigment in skin, hair, and eyes, sometimes accompanied by visual impairment. Different types of albinism are caused by various gene mutations.

According to the National Organization for Albinism and Hypopigmentation, about 1 in 18,000 to 20,000 people in the United States have a form of albinism.


What causes albinism?

Albinism is an inherited disorder that’s present at birth. Children have a chance of being born with albinism if both of their parents have albinism or both of their parents carry the gene for albinism.
The cause of albinism is a defect in one of several genes that produce or distribute melanin, the pigment that gives skin, eyes, and hair their coloring. The defect may result in the absence of melanin production or a reduced amount of melanin production.
For most types of albinism, both parents must carry the gene in order for their child to develop the condition. Most people with albinism have parents who are only carriers of the gene and don’t have symptoms of the condition.
Other types of albinism, including one that only affects the eyes, mostly occur when a birthing parent passes the gene for albinism on to a child assigned male at birth.


What are the types of albinism?

Different gene defects characterize the numerous types of albinism. Types of albinism include:

  • oculocutaneous albinism (OCA)
  • ocular albinism
  • Hermansky-Pudlak syndrome
  • Chediak-Higashi syndrome
  • Griscelli syndrome


Oculocutaneous albinism (OCA)

OCA affects the skin, hair, and eyes. Around 1 in 70 peopleTrusted Source
 have a mutation in an OCA gene.
There are several subtypes of OCA.

OCA1


Albinism OCA1, or oculocutaneous type 1, is a type of genetic disease caused by a genetic mutation. OCA1 affects the production of melanin in the skin, hair, and eyes. These individuals will have white skin, white hair, and light eyes due to a complete absence of pigment. Rawpixel.com/Shutterstock
OCA1 is caused by a defect in the tyrosinase enzyme. There are two subtypes of OCA1:

  • OCA1a. People with OCA1a have a complete absence of melanin. People with this subtype have white hair, very pale skin, and light eyes.
  • OCA1b. People with OCA1b produce some melanin. They have light-colored skin, hair, and eyes. Their coloring may increase as they age.


OCA2


Albinism OCA2, or oculocutaneous type 2, is a more common type of albinism caused by genetic mutation. OCA2 comes with some differences than OCA1. Individuals can have some pigment in skin color and hair color. OCA2 comes from mutation in the P gene, which is also associated with other rare genetic disorders such as Prader-Willi syndrome. Masego Morulane/Getty Images
OCA2 is less severe than OCA1. It’s caused by a defect in the OCA2 gene that results in reduced melanin production. People with OCA2 are born with light coloring and skin. Their hair may be yellow, blond, or light brown.
OCA2 is most common in people of African descent and Native Americans.
OCA1 and OCA2 are the most commonTrusted Source
 subtypes globally. Around 1 in 40,000 people have OCA1, and 1 in 39,000 people have OCA2.

OCA3

OCA3 is the result of a defect in the TYRP1 gene. It usually affects people with dark skin, particularly Black people in southern Africa. People with OCA3 have reddish-brown skin, reddish hair, and hazel or brown eyes.

OCA4

OCA4 is caused by a defect in the SLC45A2 protein. It results in the minimal production of melanin and commonly appears in people of East Asian descent. People with OCA4 have symptoms similar to those in people with OCA2.

Other subtypes

OCA5, OCA6, and OCA7 are very rare subtypes of OCA.
OCA5 and OCA7 have both been reported in only one family each. OCA6 has been reported in one family and one separate individual.

Ocular albinism

Ocular albinism is the result of a gene mutation on the X chromosome and occurs almost exclusively in males.
People with ocular albinism have reduced coloring in the retina and iris. The condition doesn’t affect the skin or hair.

Hermansky-Pudlak syndrome

Hermansky-Pudlak syndrome is a rare form of albinism that’s caused by a defect in one of 10 genes. It produces symptoms similar to OCA. The syndrome occurs with lung, bowel, and bleeding disorders.
It’s more common in Puerto Rico.

Chediak-Higashi syndrome

Chediak-Higashi syndrome is another rare form of albinism that’s the result of a defect in the LYST gene. It produces symptoms similar to OCA, but it may not affect all areas of the skin. There have been fewer than 500 casesTrusted Source
 reported globally.
The skin is usually creamy white to grayish. Hair is usually brown or blond with a silvery sheen. People with this syndrome have a defect in the white blood cells, increasing their risk of infections.

Griscelli syndrome

Griscelli syndrome is an extremely rare genetic disorder. It’s caused by a defect in one of three genes. There were only around 150 known cases of this syndrome worldwide between 1978 and 2018.
It occurs with albinism (but may not affect the entire body), immune issues, and neurological issues. Griscelli syndrome usually results in death within the first decade of life.

What are the symptoms of albinism?

People with albinism will have the following symptoms:

  • an absence of color in the skin, hair, or eyes
  • lighter than normal coloring of the skin, hair, or eyes
  • patches of skin that have an absence of color

Albinism occurs with vision problems, which may include:


How is albinism diagnosed?

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 a doctor or an electroretinogram test. This test measures the response of the light-sensitive cells in the eyes to reveal eye problems associated with albinism.

Is there a treatment for albinism?

There’s no cure for albinism. But treatment can help relieve symptoms and prevent sun damage.
Treatment may include:

Results from a small clinical trial (5 people) suggest that the drug nitisinone can help increase melanin in the skin and hair of people with OCA1b. More research is needed.


What’s the long-term outlook?

Most forms of albinism don’t affect a person’s life expectancy.
Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, and Griscelli syndrome do affect life expectancy. This is because of the health problems associated with the syndromes. These syndromes are all very rare.
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.


Last medically reviewed on September 22, 2021

How we reviewed this article:


SOURCES

HISTORY
Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available.
Current Version
Apr 19, 2023

Written By
Rose Kivi, Matthew Solan
Edited By
Ashley Williams
Copy Edited By
Connor Rice
Sep 22, 2021

Medically Reviewed By
Susan Bard, MD


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