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. 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. 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. White hair is characteristic of aging, but colorless hair strands can appear at any age — even while you're still in high school or college. Vitiligo is a medical condition that causes white patches on your skin. Learn about the types and patterns of this condition, and the treatment…. Here are 16 of the best sunscreens on the market in spray, lotion, and solid forms, and for different needs.
They're tried and true. Everyone can benefit from a good facial cleanser, and many products are specially formulated for dry, sensitive skin. Blue lips are most often caused when something is preventing you from getting enough oxygen into your body. Hermansky-Pudlak syndrome: This rare variant is most common in Puerto Rico. The symptoms are similar to oculocutaneous albinism but bowel, heart, kidney, and lung diseases or bleeding disorders, such as hemophilia and more likely, too.
Symptoms are similar to oculocutaneous albinism but hair can appear silvery, and the skin can look slightly gray. There may be defects in the white blood cells, making infections more common. As research continues, more specific mutations may be discovered, helping us understand the underlying causes of albinism in more detail.
Most types of albinism are inherited in an autosomal recessive inheritance pattern. The exception is X-linked ocular albinism. This is passed on in an X-linked inheritance pattern. With autosomal recessive inheritance, an individual must receive faulty copies of a gene from the mother and father to develop albinism. The parent who carries the gene often does not show symptoms. If both parents carry the gene but have no symptoms, there is a 1 in 4 chance that their offspring will have albinism.
An estimated 1 in 70 people carry the genes associated with albinism but are not affected by the mutations. Because females carry two X chromosomes, if one gene damaged, the other can often make up the shortfall. Females can still carry and pass on the gene. Men, however, have one X and one Y chromosome. This means that any albino mutations in their singular X chromosome will generate the condition.
If the mother has an X-linked mutation, each daughter will have a 1 in 2 chance of becoming a carrier and each son will have a 1 in 2 chance of developing albinism. Other diseases can also cause changes in pigmentation, but they will not cause changes in vision. If pigment changes and vision changes are both present, albinism is very likely to be the cause.
The most reliable way to diagnose albinism is with genetic testing. However, in families with a history of albinism, this is not always necessary. Procedures to minimize strabismus can make it less noticeable, but surgery will not improve vision. For couples who have not had a child with albinism, there is no simple test to determine whether a person carries a gene for albinism.
Researchers have analyzed the DNA of many people with albinism and found the changes that cause albinism, but these changes are not always in exactly the same place, even for a given type of albinism. Moreover, many of the tests do not find all possible changes. Therefore, the tests for the albinism gene may be inconclusive. If parents have had a child with albinism previously, and if that affected child has had a confirmed diagnosis by DNA analysis, there is a way to test in subsequent pregnancies to see if the fetus has albinism.
The test uses either amniocentesis placing a needle into the uterus to draw off fluid or chorionic villous sampling CVS. Cells in the fluid are examined to see if they have an albinism gene from each parent.
For specific information and genetic testing, seek the advice of a qualified geneticist or genetic counselor. Those considering prenatal testing should be made aware that people with albinism usually adapt quite well to their disabilities and lead very fulfilling lives. Eye problems in albinism result from the abnormal development of the eye because of a lack of pigment and often include:. The iris, the colored area in the center of the eye, has very little or no pigment to screen out stray light coming into the eye.
Light normally enters the eye only through the pupil, the dark opening in the center of the iris, but in albinism light can pass through the iris as well. For the most part, treatment consists of visual rehabilitation. Surgery to correct strabismus may improve the appearance of the eyes. However, since surgery will not correct the misrouting of nerves from the eyes to the brain, surgery will not improve eyesight or fine binocular vision. Surgical intervention is also available to minimize nystagmus.
People with albinism are sensitive to glare, but they do not prefer to be in the dark, and they need light to see just like anyone else. Sunglasses or tinted contact lenses may help outdoors. Indoors, it is important to place lights for reading or close work over a shoulder rather than in front. Various optical aids are helpful to people with albinism, and the choice of an optical aid depends on how a person uses his or her eyes in jobs, hobbies or other usual activities.
Frequency Overall, an estimated 1 in 20, people worldwide are born with oculocutaneous albinism. Inheritance Oculocutaneous albinism is inherited in an autosomal recessive pattern , which means both copies of a gene in each cell have mutations. Research Studies from ClinicalTrials. References Brilliant MH. The mouse p pink-eyed dilution and human P genes, oculocutaneous albinism type 2 OCA2 , and melanosomal pH. Pigment Cell Res.
Orphanet J Rare Dis. Oculocutaneous Albinism Type 4. Oculocutaneous albinism type 4 is one of the most common types of albinism in Japan. Am J Hum Genet. Epub Feb Mutational analysis of oculocutaneous albinism: a compact review. Biomed Res Int. Epub Jun
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