Healthy Living

What Causes Albinism?

What Causes Albinism?

What is albinism?

Albinism is a group of genetic disorders that cause little or no production of the natural pigment called melanin. The color of your skin, hair, and eyes depend on the type and amount of melanin produced by your body. Most individuals with albinism have sun sensitivity, which makes them more susceptible to developing skin cancer

One of the common myths about individuals with albinism is having red eyes. Their eyes may look reddish or violet due to lighting conditions that allow the blood vessels to be seen. It is important to note that the amount of pigment in the eyes varies, and that there are different types of albinism. Vision problems, however, are associated with albinism. 

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Around one out of every 20,000 people in the US is born with a form of albinism according to the National Organization for Albinism and Hypopigmentation (NOAH). Even though there is no cure for albinism, there are steps that can be taken to protect the skin and maximize one’s vision. 

Signs and Symptoms

The signs of albinism can be seen on an individual’s skin, hair, and eye color. Although the signs may not always be obvious, those who have albinism tend to always have vision problems. 

Skin

People with albinism tend to have a skin color ranging from white to brown. They may also have the same skin color of their siblings or parents without the disorder. The most distinguishable form of albinism is having white hair with very pale or pinkish skin.

The skin color of some individuals with albinism never changes. Other people with albinism may have an increase in the production of melanin, which leads to small pigmentation changes.  These changes may occur during childhood until teenage years. When sun exposure, some individuals may develop small to large freckles, moles with or without pigment, and the ability to tan.

Hair

Hair color in albinism usually ranges from very pale skin to brown. Those who have Asian or African descent may have brown, reddish, or yellow hair color. There is also a possibility of developing a darker hair color during early adulthood. 

Eye Color

Eye color may change as an individual gets older, but most people with albinism have very light blue to brown eyes. Their eyes seem translucent because they lack a pigment in their irises, which is the colored part of the eyes. Individuals with very light eyes may appear with red eyes in some lighting since their irises cannot fully block the light from entering their eyes. 

Vision

Vision problems may occur with albinism, which include:

  • Nystagmus – rapid, involuntary eye movements
  • Strabismus – abnormal eye alignment (crossed eyes)
  • Photophobia – extreme sensitivity to light
  • Astigmatism a spherical curvature deviation that causes blurred vision

Vision problems related to albinism tend to worsen in newborn babies, but also improve very fast in the first six months. 

Causes

Albinism is a genetic disorder caused by a mutation in one of several genes. During melanin production, each gene gives instructions for the production of one of several proteins. Melanin is produced by melanocytes, which are cells found in the eyes and skin. If there is no melanin produced, or when there is a considerable decrease in the amount of melanin, a mutation may result.

In some forms of albinism, an individual must receive two mutated genes from his parents (one mutated gene from each parent) to develop albinism. This pattern is called as recessive inheritance. 

Regardless of the type of gene mutation, all types of albinism have vision problems. Impaired vision is usually caused by abnormal optic nerve pathway development from the eye to the brain and from abnormal retinal development. 

Albinism Inheritance

Most people with albinism inherit an autosomal recessive pattern, except for those who have ocular albinism, who inherit an X-linked inheritance pattern. 

  • Autosomal Recessive Inheritance Pattern - In an autosomal recessive inheritance, individuals must inherit faulty gene copies from each parent for albinism to develop. There is a 1 in 4 chance that a person will have albinism if both parents carry the gene, and a 1 in 2 chance of becoming an asymptomatic carrier. In fact, approximately 1 out of 70 people carry genes involved in albinism without mutations. 
  • X-linked Inheritance Pattern - Males are mostly affected by X-linked recessive conditions. However, females can be still carriers of the gene. Females have two X chromosomes, and if one gene is damaged, the other gene can make up the shortfall. When it comes to males, they have one X and one Y chromosome. Thus, any albino mutations in their single X chromosome will result in the condition. A mother with an X-linked mutation will have a 1 in 2 chance of having a carrier daughter and a 1 in 2 chance of having a son with albinism. 

Types of Albinism

The types of albinism are usually based on the specific mutated gene that caused the disorder. They include:

1. Oculocutaneous Albinism or OCA

OCA is caused by 1 of 4 genetic mutations. It is further divided into seven types according to mutations. Subdivisions include:

  • OCA Type 1 - Individuals with OCA type 1 are usually born with white hair, milky skin, and blue eyes. Some individuals with this type of albinism do not have skin pigmentation changes. However, during early childhood, others may start to produce melanin. They may experience a change in their hair color from white to brown, blond, or red. Their irises may also change in color with lesser translucence. 
  • OCA Type 2 - OCA type 2 is less severe than OCA type 1. It is commonly seen among Native Americans, African-Americans, and sub-Saharan Africans. Their skin may develop freckles and moles over time when exposed to the sun. Their hair may turn red, auburn, or yellow. They can have tan or bluish gray eyes along with white skin at birth. 
  • OCA Type 3 - This type is caused when there is a defect in the TYRP1 gene. It commonly affects individuals who are dark-skinned, mostly black South Africans. Individuals with OCA type 3 have a reddish-brown skin, reddish hair, and hazel or brown eyes.
  • OCA Type 4 - This type is often caused by a defect in the SLC45A2 gene. In this case, the body produces a minimal amount of melanin. It mostly occurs in people from the East Asian regions. Its symptoms are often the same as those individuals with OCA type 2.

2. Ocular Albinism or OA

Ocular albinism is a result of a gene mutation on the X chromosome. This problem mostly occurs in males and tends to only affect the eyes. Individuals with OA have normal skin, hair, and eye color, but do not have color in the retina, which lines the back of the eyes.

3. Chediak Higashi Syndrome

It is a rare form of albinism that involves a LYST gene mutation. Individuals with Chediak-Higashi syndrome have similar signs and symptoms to oculocutaneous albinism, wherein the color of their hair range from blonde to brown along with having a grayish or creamy white skin. Moreover, people with this disorder also have a white blood cell defect, which make them more susceptible to developing infections. 

4. Hermansky-Pudlak Syndrome or HPS

It is a very rare albinism disorder, which is caused by a mutation in one of eight different genes. Hermansky–Pudlak syndrome is more commonly observed in Puerto Rico. The signs and symptoms of this disorder are similar to those who have oculocutaneous albinism. However, individuals with this disorder may also develop blood clotting problems, lung disease, and bowel diseases. 

5. Griscelli Syndrome

Griscelli syndrome is an extremely rare genetic disorder caused by a defect in 1 of 3 genes. Since 1978, there are only 60 reported cases of Griscelli syndrome all over the world. This disorder is usually accompanied by albinism, neurological problems, and immune system disorders. Individuals with this genetic disorder usually have a life expectancy of 10 years. 

Treatment 

Albinism is a genetic disorder, which is why treatment is limited. However, people with albinism can get proper eye and skin care to monitor any abnormalities. For eye health, there may be a need for prescription lenses and yearly eye examinations. Even though surgery is rarely a treatment method for albinism, your ophthalmologist may recommend it to minimize nystagmus.

Yearly skin assessments must also be done to effectively screen for skin cancer and skin lesions that can result in the development of cancer. 

Key Takeaways

  • Albinism is a group of genetic disorders that cause little or no production of the natural pigment called melanin. 
  • The color of your skin, hair, and eyes depend on the type and amount of melanin produced by your body.
  • Albinism has no cure. It is a genetic disorder, which is why treatment is limited.