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. The level of success in reducing symptoms varies between individuals. Albinism does not worsen with age. A child with albinism can flourish and achieve the same education and employment as a person without the condition. The most common physical problems associated with albinism are the increased risk of sunburn and skin cancers.
These may include bullying at school. The person may be made to feel like an outsider because they look different. These social factors can lead to stress , low self-esteem, and isolation. A study carried out in Nigeria reported that they:.
Furthermore, affected individuals were less likely to complete schooling, find employment and find partners. In some sub-Saharan countries, such as Tanzania and Burundi, the body parts of individuals with albinism are sought after by witch doctors.
There have been numerous cases of children with albinism being murdered for profit. In some African countries, Tanzania and Zimbabwe particularly, some people believe that having sex with a woman with albinism cures AIDS. This false belief has led to murder, rape, and additional AIDS infections. Different skin types require different skin care products. Individuals normally have two copies of each numbered chromosome and the genes on them — one inherited from the father, the other inherited from the mother.
Neither of these gene copies is functional in people with albinism. Each unaffected parent of an individual with an autosomal recessive condition carries one functional copy of the causative gene and one nonfunctional copy. They are referred to as carriers , and do not typically show signs or symptoms of the condition.
Both parents must carry a defective OCA gene to have a child with albinism. Ocular albinism type 1 is inherited in an X-linked pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome , one of the two sex chromosomes. In males who have only one X chromosome and one Y , one altered copy of the causative gene in each cell is sufficient to cause the characteristic features of ocular albinism, because males do not have another X chromosome with a working copy of the gene.
Because females have two copies of the X chromosome, women with only one copy of a mutation in each cell usually do not experience vision loss or other significant eye abnormalities. They may have mild changes in retinal pigmentation that can be detected during an eye examination.
In addition to albinism, HPS is associated with bleeding problems and bruising. Some forms are also associated with lung and bowel disease. Do you have updated information on this disease?
We want to hear from you. Treatment Treatment. This can be done by: [2] [3] avoiding prolonged exposure to the sun, using sunscreen with a high SPF rating 20 or higher , covering up completely with clothing when exposed to the sun, and wearing sunglasses with UV protection. Individuals with vision problems may need corrective lenses.
They should also have regular follow-up exams with an ophthalmologist. In rare cases, surgery may be needed. Individuals with albinism should also have regular skin assessments to screen for skin cancer or lesions that can lead to cancer. Prognosis Prognosis. Most people with albinism live a normal life span and have the same types of medical problems as the rest of the population.
Research Research. Clinical Research Resources ClinicalTrials. Click on the link to go to ClinicalTrials. Please note: Studies listed on the ClinicalTrials. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.
Organizations Organizations. Organizations Supporting this Disease. Organizations Providing General Support. Do you know of an organization? Living With Living With. Community Resources The Job Accommodation Network JAN has information on workplace accommodations and disability employment issues related to this condition. Department of Labor. Learn More Learn More. DermNet NZ provides information about this condition.
Description Oculocutaneous albinism is a group of conditions that affect coloring pigmentation of the skin, hair, and eyes. 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 Increasing the complexity: new genes and new types of albinism. Pigment Cell Melanoma Res. Epub Oct Oculocutaneous albinism type 1: the last years.
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