Albinism
Related Terms
AIED, Aland Island eye disease (X-linked), albinism, albinoidism, albinoism, autosomal dominant albinism, autosomal recessive forms of ocular albinism, black locks-albinism-deafness of sensoneural type (BADS), brown albinism, Chediak-Higashi syndrome, congenital achromia, Cross syndrome, Forsius-Eriksson syndrome (X-linked), Hermansky-Pudlak syndrome, hypopigmentation, Nettleship Falls syndrome (X-linked), ocular albinism, oculocutaneous albinism, rufous albinism, tyrosinase negative albinism (type I), tyrosinase positive albinism (type II), yellow mutant albinism.
Background
Albinism refers to a group of inherited conditions marked by decreased or absent pigmentation (coloring) of the skin, hair, and eyes. In some cases, albinism includes other eye problems, such as decreased vision, sensitivity to light, involuntary eye movements, problems with the iris (the colored part of the eye), and decreased pigment in the retina (the cells at the back of the eye that detect light).
Albinism is an inherited condition, meaning that it is passed from parents to children. Individuals receive two copies of most genes, one from the mother and one from the father. Albinism is caused by mutations in genes that provide instructions for making melanin, the pigment that provides color to hair, skin, and eyes. Melanin also absorbs ultraviolet light from the sun to protect the skin. Because melanin is absent or decreased, people with albinism are at increased risk of skin damage caused by the sun.
Because different mutations affect the production of melanin in slightly different ways, the type of albinism is determined by the specific genetic mutation that is present. The different types of albinism include oculocutaneous albinism (OCA) types 1, 2, 3, and 4; ocular albinism (OA); Chediak-Higashi syndrome (CHS); Hermansky-Pudlak syndrome (HPS); and Griscelli syndrome (GS).
The worldwide prevalence of OCA type 1 is about one in 40,000. The worldwide prevalence of OCA type 2 is about one in 15,000. The worldwide prevalence of OCA type 3 is unknown. OCA type 4 is extremely rare, except in Japan, where it accounts for about 24% of cases of OCA. The worldwide prevalence of OA is about one in 50,000. CHS and GS are extremely rare, with unknown prevalence. HPS is rare, except in Puerto Rico, where its prevalence is about one in 1,800.
Albinism generally affects males and females in equal numbers. One exception is OA, which is far more common in males. Albinism generally affects people of all races and ethnicities equally. Exceptions include OCA type 2, which is more common among Africans and African-Americans than among Caucasians, and OCA type 3, which has been confirmed only in Africans and African-Americans.
Most people with albinism live long, normal lives. OCA types 1, 2, 3, and 4 are not associated with premature death, and complications are typically limited to skin and vision problems.
People with CHS may bruise and bleed easily and are prone to lung and sinus infections. About 85% of people with CHS experience severe complications and may die by age 10. People with HPS often have bleeding problems, lung problems, heart conditions, and kidney problems. Lung problems often cause death by the fourth or fifth decade of life. People with GS have weakened immune systems and typically die from infections during the first decade of life.
Signs and symptoms
General: Albinism is caused by mutations or defects in genes that provide instructions for making proteins that create melanin. Melanin is the pigment that provides color in the skin, hair, and eyes. Melanin also provides protection from the harmful ultraviolet rays of the sun. When these genes are mutated, melanin is not produced properly. This lack of melanin is apparent at birth.
Eyes: People with albinism often have very light-colored eyes because of a lack of the pigment melanin. The eyes require melanin to function normally. Because people with albinism do not have adequate melanin, vision is impaired. Decreased vision is caused primarily by underdevelopment of part of the retina, a condition known as foveal hypoplasia. Other common vision problems in people with albinism include extreme farsightedness, nearsightedness, and astigmatism.
In farsightedness, a person can see objects at a distance but cannot clearly see objects in close proximity. In nearsightedness, a person can see close objects but cannot clearly see objects at a distance. Astigmatism refers to abnormal curvature of the cornea, the transparent front portion of the eye. Individuals with this condition have blurry or wavy vision. In addition, people with albinism may have nystagmus (involuntary movements of the eyes), strabismus (crossed eyes), and photophobia (sensitivity to bright light).
Hair: Melanin provides color to the hair on the scalp and body. Because people with albinism lack or have decreased amounts of melanin, their hair lacks pigmentation and appears white or very light blonde.
Skin: People with albinism have very fair skin; in some cases, it is a milky-white color. The skin requires melanin for protection from the harmful ultraviolet (UV) rays of the sun. Because people with albinism do not have adequate amounts of melanin, they are prone to sun-related skin damage such as sunburn and skin cancer.
Diagnosis
Physical exam: A thorough physical exam and family history should be conducted. Patient interview questions should focus on sensitivity to the sun and sunburn, bleeding, and bruising. In particular, a clinician should look for the presence of distinctive features present in the skin, hair, and eyes.
Skin biopsy: A skin biopsy is often done to diagnose albinism. A skin biopsy involves removal of a small sample of tissue, which is then analyzed in a laboratory.
Eye exam: An eye exam can help diagnose the various forms of albinism. In particular, an ophthalmologist (eye doctor) should evaluate patients suspected of having albinism for the condition of the retina, the presence of melanin, the color of the iris, nystagmus (involuntary movements of the eyes), astigmatism, farsightedness, nearsightedness, strabismus (crossed eyes), and sensitivity to light.
Hair bulb tyrosinase assay: A hair bulb tyrosinase assay can help distinguish the type of albinism. In this test, hair bulbs or roots from the scalp are plucked and placed in a solution containing dihydroxyphenylalanine (L-DOPA). In people with OCA type 1, the hair bulb remains white. Hair bulbs from people with other forms of albinism turn dark.
Genetic testing: Genetic tests may be performed to confirm a diagnosis of albinism. A sample of the patient's blood is taken and analyzed in a laboratory for defects in the specificgenes known to cause albinism. If one of these defects is detected, a positive diagnosis is made.
Prenatal DNA testing: If there is a family history of albinism, prenatal testing may be performed to determine whether the fetus has the disorder. Amniocentesis and chorionic villus sampling (CVS) can diagnose albinism. However, because there are risks associated with these tests, patients should discuss the potential health benefits and risks with a medical professional.
During amniocentesis, a long, thin needle is inserted through the abdominal wall and into the amniotic cavity (the sac surrounding the fetus within the uterus), and a small amount of fluid is removed. Cells in the fluid are then analyzed for normal and abnormal chromosomes. This test is usually performed between 14 and 20 weeks of pregnancy. At some facilities, it can be performed as early as 11 weeks. The risk of miscarriage is about one in 200-400. Some patients may experience minor complications, such as cramping, leaking fluid, or irritation where the needle was inserted.
During chorionic villus sampling (CVS), a small piece of tissue (chorionic villi) is removed from the placenta between the ninth and 14th weeks of pregnancy. CVS may be performed through the cervix (opening of the uterus) or through the abdomen. The cells in the tissue sample are then analyzed for the mutated gene. Miscarriage occurs in about 0.5-1% of women who undergo this procedure.
Complications
Psychosocial issues: People with albinism may experience psychosocial issues such as depression because of their different physical appearance.
Skin cancer: Because their skin is more easily damaged by sun exposure, people with albinism are at increased risk of skin cancer.
Sunburn: People with albinism lack the dark pigment that protects the skin from the harmful ultraviolet (UV) rays of the sun. This places them at higher risk of sunburn, even if sun exposure is brief.
Vision problems: Because of a variety of eye problems, including abnormal curvature of the cornea and involuntary eye movements, people with albinism often have impaired vision. Vision problems can range from mild to severe.
Other: People with Chediak-Higashi syndrome (CHS) may bruise or bleed easily, and many have recurrent lung and sinus infections. In the accelerated phase of the disease, during which the disease rapidly progresses and worsens, individuals with CHS may experience fever, decreased numbers of certain blood cells, enlarged spleen and liver, jaundice, and nerve problems. Long-term complications for people with Hermansky-Pudlak syndrome (HPS) may include gum disease and problems with the lungs, kidneys, and digestive tract.
Treatment
General: There is no cure for albinism. Treatment aims to reduce symptoms and prevent complications. In many cases, treatment may not be needed.
Antibiotics: For people with albinism who are prone to infection, antibiotics may be prescribed for short-term or long-term use.
Corrective lenses: Vision can be improved by the use of corrective lenses. In addition, sensitivity to bright light may be improved by wearing tinted lenses. In cases of severe visual impairment, bifocals or bioptics (telescopic lenses mounted on glasses) may be prescribed. Strabismus (crossed eyes) may be treated early in life by placing a patch over one eye to promote the use of the less active eye.
Sunscreen: There is no treatment for lack of pigment in the skin of people who have albinism. However, because they are at increased risk for sunburn and skin cancer, people with albinism should wear a broad-spectrum sunscreen on all exposed areas of the body, including the scalp. Special clothing that increases protection from the sun is also available and includes hats, visors, long-sleeve shirts, and long pants.
Surgery: In severe cases, eye muscle surgery may be done to treat nystagmus (involuntary eye movements) or strabismus (crossed eyes).
Visual aids: Various visual aids can be used to meet the individual needs of people with albinism. These may include large-print books and other reading materials, high-contrast written materials, hand-held monoculars, video enlargement machines, and other types of magnifiers. In addition, children and adults attending school may benefit from a printed copy of the teacher's board notes. People with albinism may also benefit from various specialized computer programs that address their individual needs.
Transplantation: People with Chediak-Higashi syndrome (CHS) may benefit from bone marrow, blood, or platelet transplantation, which can improve bleeding and immune system problems. Transplantation surgeries carry some risk and should be regarded as a viable option only in severe cases.
Integrative therapies
Note: Currently there are limited scientific data on the use of integrative therapies for the treatment or prevention of albinism. The therapies listed below have been studied for related conditions such as sunburn and skin cancer. The integrative therapies listed below should be used only under the supervision of a qualified healthcare provider and should not be used in replacement of other proven therapies.
Unclear or conflicting scientific evidence:
Chlorella: Early studies suggest a potential effect of chlorella on skin cancer. Avoid with known allergy or hypersensitivity to chlorella, its constituents, or members of the Oocystaceae family. Children have been found to be allergic to chlorella. Chlorella has a high vitamin K content and may decrease the effectiveness of anticoagulants (blood thinners) such as warfarin. Long-term consumption of chlorella may cause manganese-induced parkinsonism. Other adverse effects include photosensitivity, occupational asthma, and fatigue.
Green tea: There is limited animal and human research on green tea as a protective agent from ultraviolet light injury to the skin. Some studies have found conflicting results. Comparisons have not been made with well-established forms of sun protection, such as ultraviolet-protective sunscreen. The effects of green tea on skin damage caused by the sun remain unclear. Avoid if allergic or hypersensitive to caffeine or tannin. Use cautiously with diabetes or liver disease.
Lutein: Numerous laboratory studies have shown the antioxidant effects of lutein. More research is required on the use of lutein for sunburn prevention before a firm conclusion can be made. Avoid if allergic or hypersensitive to lutein or zeaxanthin. Use cautiously if at risk for cardiovascular disease or cancer. Avoid if pregnant or breastfeeding.
Lycopene: Lycopene, in combination with other carotenoids, such as beta-carotene, vitamins C and E, selenium, and proanthocyanidins, may help in reducing sunburn. Selected protective effects from ultraviolet (UV) rays have been observed in small, short-term studies. More research is needed before a firm conclusion can be drawn. Avoid if allergic to tomatoes or to lycopene. Avoid if pregnant or breastfeeding.
Para-aminobenzoic acid (PABA): PABA is best known for its topical use as a component of sunscreen products. Although PABA and related compounds have frequently been used as topical sunscreen agents, only a few studies in the literature have demonstrated its effectiveness for this specific purpose. Further studies may help to elucidate the protective properties of PABA. Its use as a component of sunscreens has diminished recently, because of reports of frequent allergic reactions and cross-sensitivity with other medications.
Pycnogenol?: Pycnogenol? taken by mouth may reduce redness of the skin caused by solar ultraviolet light. Further research is needed before a recommendation can be made. Avoid if allergic or hypersensitive to Pycnogenol?, its components, or members of the Pinaceae family. Use cautiously with diabetes, hypoglycemia, and bleeding disorders. Use cautiously if taking medications that reduce blood cholesterol levels, medications that may increase the risk of bleeding, medications that lower blood pressure, or drugs that affect the immune system. Avoid if pregnant or breastfeeding.
Selenium: Protection from UV damage was initially observed in early research using selenium and other antioxidant supplementation, although there is some evidence that selenium does not prevent light-induced skin redness. Avoid if allergic or sensitive to products containing selenium. Avoid with history of nonmelanoma skin cancer. Selenium is generally regarded as safe for pregnant or breastfeeding women. However, animal research reports that large doses of selenium may lead to birth defects.
Vitamin A: It is unclear whether vitamin A or beta-carotene, taken by mouth or used on the skin with sunscreen, is beneficial in the prevention or treatment of skin cancers or wrinkles. Avoid if allergic or hypersensitive to vitamin A. Vitamin A toxicity can occur if taken at high dosages. Use cautiously with liver disease or alcoholism. Smokers who consume alcohol and beta-carotene may be at increased risk for lung cancer or heart disease. Vitamin A appears safe in pregnant women if taken at recommended doses. However, excess or inadequate vitamin A has been associated with birth defects. Excessive doses of vitamin A have been associated with central nervous system problems. Use cautiously if breastfeeding, because the benefits or dangers to nursing infants have not been clearly established.
Fair negative scientific evidence:
Selenium: Results from the Nutritional Prevention of Cancer (NPC) trial, conducted among 1,312 Americans over a 13-year period, suggest that selenium supplementation given to individuals at high risk of nonmelanoma skin cancer is ineffective in the prevention of basal cell carcinoma and actually increases the risk of squamous cell carcinoma and total nonmelanoma skin cancer. Therefore, selenium supplementation should be avoided in individuals at risk for or with a history of nonmelanoma skin cancer. Avoid if allergic or sensitive to products containing selenium. Avoid with a history of nonmelanoma skin cancer. Selenium is generally regarded as safe for pregnant or breastfeeding women. However, animal research reports that large doses of selenium may lead to birth defects.
Prevention
General: Because albinism is inherited, there is currently no known way to prevent the condition. However, a number of options are available for prospective parents with a family history of albinism.
Genetic testing and counseling: Individuals who have albinism may meet with a genetic counselor to discuss the risks of having children with the disease. Individuals with a family history of albinism may meet with a genetic counselor to determine whether they carry any defective genes. Carriers can be determined through detailed family histories or genetic testing.
Known carriers of genes that cause albinism may undergo genetic counseling before they conceive a child. Genetic counselors can explain the options and the associated risks of various tests, including preimplantation genetic diagnosis (PGD), amniocentesis, and chorionic villus sampling (CVS).
Preimplantation genetic diagnosis (PGD) may be used with in vitro fertilization (IVF). In PGD, embryos are tested for the defective genes, and only the embryos that are not affected may be carried to term. Because albinism can be detected in a developing fetus, parents may choose whether to continue the pregnancy. Genetic counselors may assist parents with these difficult decisions.
Author information
This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
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Causes
Genetic mutations: Albinism is an inherited condition, meaning that it is passed from parents to children. Individuals receive two copies of most genes, one from the mother and one from the father. Albinism is caused by mutations or defects in genes that provide instructions for making proteins essential to the production of melanin, the pigment that provides color in the skin, hair, and eyes. Melanin also protects the skin from the harmful ultraviolet rays of the sun. When these genes are mutated, melanin is not produced properly.
The type of albinism is determined based on the specific genetic mutation that is present. The different types of albinism include oculocutaneous albinism (OCA) types 1, 2, 3, and 4; ocular albinism (OA); Chediak-Higashi syndrome (CHS); Hermansky-Pudlak syndrome (HPS); and Griscelli syndrome (GS).
OCA 1 is caused by mutations in the tyrosinase (TYR) gene OCA 2 by mutations in the P gene OCA 3 by mutations in the TRP1 gene and OCA type 4 by mutations in the MATP gene. HPS is caused by mutations in the HPS gene CHS by mutations in the CHS gene (also known as the LYST gene) OA by mutations in the OA1 gene (also known as GPR143) and GS by mutations in the RAB27A and the MYO5A genes. While the functions of some of these genes are better defined than others, they all provide instructions for making proteins important to the normal production and function of melanin.
Autosomal recessive inheritance: Most types of albinism are inherited as autosomal recessive traits. Therefore, a person must inherit two copies of the defective gene (one from each parent) in order to have the disease. Individuals who inherit only one copy of the defective gene generally have no symptoms and are called carriers, because they can pass the disorder on to their children.
If one parent is a carrier, or has only one copy of the defective gene, then each child will have a 50% chance of inheriting one defective gene and being a carrier. If both parents are carriers, each child has a 25% chance of inheriting two defective genes, a 50% chance of inheriting only one defective gene, and a 25% chance of inheriting neither defective gene. Therefore, if both parents are carriers, about one out of four children will have the disorder.
X-linked recessive inheritance: One type of albinism, ocular albinism (OA), is inherited as an X-linked recessive trait. Females have two copies of the X chromosome, while males have one X and one Y chromosome. Males always inherit an X chromosome from the mother and a Y chromosome from the father; therefore, a male can inherit an X-linked trait only from the mother. A female needs to inherit two mutated copies (one from each parent) of the OA1 gene to develop OA, while a male needs to inherit only one mutated copy of the gene to develop the condition. Therefore, OA is much more common among males than females. Females who inherit only one mutated copy of the gene are called carriers, because they can pass the disorder on to their children.
Risk factors
Because albinism is inherited, the only known risk factor is a family history of the disorder. Albinism generally affects males and females in equal numbers. Ocular albinism (OA) almost exclusively affects males. However, females may carry the defective gene.
Albinism generally affects people of all races and ethnicities equally. Exceptions include OCA type 2, which is more common among Africans and African-Americans than among Caucasians, and OCA type 3, which has been confirmed only in Africans and African-Americans.
The prevalence of oculocutaneous albinism (OCA) type 1 is about one in 40,000. The prevalence of OCA type 2 is about one in 15,000. The prevalence of OCA type 3 is unknown. OCA type 4 is extremely rare, except in Japan, where it accounts for about 24% of cases of OCA. The prevalence of OA is about one in 50,000. Chediak-Higashi syndrome (CHS) and Griscelli syndrome (GS) are extremely rare, with unknown prevalence. Hermansky-Pudlak syndrome (HPS) is rare, except in Puerto Rico, where its prevalence is about one in 1,800.
Types of the disease
General: The type of albinism is determined based on the specific genetic mutation that is present. The different types of albinism include oculocutaneous albinism (OCA) types 1, 2, 3, and 4; ocular albinism (OA); Chediak-Higashi syndrome (CHS); Hermansky-Pudlak syndrome (HPS); and Griscelli syndrome (GS).
Oculocutaneous albinism type 1: OCA type 1 is caused by mutations in the tyrosinase (TYR) gene. This gene provides instructions for making an enzyme necessary for the production of melanin. OCA type 1 is inherited as an autosomal recessive trait. People who have OCA type 1 have white hair, milky white skin, and blue eyes.
OCA type 1 is divided into two subtypes: type 1A and type 1B. OCA 1A, also known as classic tyrosinase-negative OCA, is the most severe form of OCA. People with OCA 1A have white hair and skin and blue eyes. These individuals are at high risk of sunburn and skin cancer. People with OCA 1A have extremely poor vision. In addition, sensitivity to light and involuntary movement of the eyes can be severe in this form of OCA.
OCA type 1B is also called yellow mutant OCA, Amish albinism, or xanthous albinism. Although they are typically born with complete lack of pigment, individuals with OCA 1B may have pigmentation that ranges from very little to near normal. People with OCA 1B tend to show more pigment during the first few years of life, with yellow hair pigment and eyelashes that may be darker than the hair on the scalp. The eyes may be hazel or light brown. Vision may be moderately impaired and may improve with age. People with OCA 1B may also develop nevi, harmless pigmented lesions on the skin.
A subtype of OCA 1B is temperature-sensitive OCA 1B. In this form of OCA, the enzyme involved in melanin creation has different activity in different parts of the body depending upon their temperature. Melanin is produced in cooler areas of the body; therefore, the arms and legs tend to have darker pigment, whereas warmer parts of the body (i.e., those closer to the heart) do not have melanin activity and are therefore lighter in color.
Oculocutaneous albinism type 2: OCA type 2 is the most common type of albinism in all races and is caused by mutations in the P gene. The P gene provides instructions for making a protein essential to the production of melanin, although its exact role is not yet known. OCA type 2 is inherited as an autosomal recessive trait. Most people with OCA type 2 do not have any black pigment in the skin, hair, or eyes at birth. Pigmentation and vision may improve with age.
Caucasians with OCA type 2 may have a range of pigmentation at birth. The hair may be light yellow or dark blond. The skin tends to be white and does not tan. The eyes tend to be blue-gray. Africans and African-Americans with OCA type 2 usually have yellow hair at birth that remains this color throughout life. The skin is white and does not tan, and the eyes are blue-gray.
A subtype of OCA type 2 is brown OCA, which is seen only in Africans and African-Americans. In this type of OCA, the skin and hair are light brown and the eyes are gray. Hair and eye color may darken with time.
Oculocutaneous albinism type 3: OCA type 3 is caused by mutations in the tyrosinase-related protein-1 (TRP1) gene. This gene provides instructions for making a protein essential to the production of melanin, although its exact role is not yet known. OCA type 3 is inherited as an autosomal recessive trait and may be referred to as red, rufous, or xanthous albinism. In this form of OCA, black pigment is typically replaced with brown pigment. African people with OCA type 3 tend to have light brown or reddish skin and hair and blue-brown eyes. People with this type of OCA may also have eye problems.
Oculocutaneous albinism type 4: OCA type 4 is caused by mutations in the membrane-associated transporter protein (MATP) gene. The function of the protein created by this gene is not clear. OCA type 4 is inherited as an autosomal recessive trait. OCA type 4 may be the most common form of albinism seen in people from Japan and Korea. However, information concerning this type of OCA is currently limited.
Ocular albinism: OA is caused by mutations in the OA1 gene (also called GPR143), which is located on the X chromosome. The role of the protein created by the OA1 gene is currently unknown. OA is an X-linked recessive trait that primarily affects the eyes. Eye problems are similar to those seen in OCA. Males are primarily affected by OA, because a female must carry the genes on both X chromosomes in order to have the condition. People with this type of albinism are often identified by the presence of macromelanosomes, which are dense collections of melanin in the skin that can be detected with a biopsy.
Chediak-Higashi syndrome (CHS): CHS is caused by mutations in the LYST gene (also known as the CHS1 gene). This gene provides instructions for making a protein important for the normal functioning of melanin cells. CHS is inherited as an autosomal recessive trait. People with CHS are at an increased risk of infections, especially of the lungs, nose, sinuses, and throat. Hair, skin, and eye pigment tends to be reduced, but albinism is not obvious. The hair may be light brown to blonde in color and have a metallic sheen, the skin may be creamy white to gray, and eye problems are variable.
Hermansky-Pudlak syndrome (HPS): HPS is caused by mutations in the HPS gene. There are eight distinct types of HPS, all of which are inherited as autosomal recessive traits. People with HPS have pigmentation that ranges from none to near normal. Other symptoms include involuntary eye movements, crossed eyes, underdevelopment of part of the retina, and decreased vision. Abnormal bleeding may occur in infants with HPS (in males, this is often discovered at the time of a circumcision). Throughout life, people with HPS are more susceptible to bleeding and bruising. Later in life, people with HPS may experience lung problems, inflammatory bowel disease, kidney problems, and a heart condition called cardiomyopathy.
Griscelli syndrome (GS): GS is caused by mutations in the RAB27A gene, which provides instructions for making the GTP-binding protein RAB27a, and the MYO5A gene, which provides instructions for making the myosin motor protein myosin 5a. These proteins are important for the proper production and transport of melanin. GS is inherited as an autosomal recessive trait. People with GS tend to have a milder form of albinism, with pale skin and silvery gray hair at birth.