Albinism Essay Research Paper The word albinism

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Albinism Essay, Research Paper The word albinism refers to a group of inherited conditions. People with albinism have little or no pigment in their eyes, skin, or hair. Recently a test has been developed to identify carriers of the gene for ty-neg albinism and for other types in which the tyrosianase enzyme does not function. The test uses a sample of blood to identify the gene for the tryrosinase enzymes by its code in DNA. The above test does not apply to to one type of albinism, called X-linked ocular albinism. For X-linked inheritance, the gene for albinism is located on an X chromosome. Females have two X chromosomes, while males only have one X and one Y chromosome. This X-linked albinism accurs exclusively in males. The gene is passed from mothers who carry it to their

sons. The mothers have subtle eye changes which an ophthalmogist could identigy, but mothers usually have normal vision. For each son born to a mother who carries the gene, there is one in two chance of having X-linked ocular albinism. The description is a hereditary deficiency pigmentation. This could involve the entire body or part of the body. This is believed to be caused by an enzyme deficiency involving the metabolism of melanin during prenatal development. This can be inherited by an dominant or recessive trait. In complete albinism, there is lack of pigmentation in skin and hair, as well as in retinal and iris tissue; in incomplete albinism, skin and hair may vary from pale to normal; in ocular albinism, function may vary from norma to impaired. Impairments may involve

the retina and iris. If a person has albinism then they usually have somewhere between 20/70 and 20/200 visual. Ty-Neg albinism or also called type 1A results from a genetic defect in an enzyme called tyrosinase. Tyrosinase helps the body to change the amino acid tyrosine into pigment. An amino acid is a building block of protien. Albinism is passed from parent to their kid through genes. For nearly all types of albinism both parent must carry an albinism gene to have a child with albinism. Parents may have normal pigmentation but still carry the gene. When both parents carry the gene, there is a one in four chance at each pregnancy that the baby will be born with albinism. This type of inheritance is called autosomal recessive inheritance. Eye conditions common in albinism

include: ? Nystagmus, irregular rapid eye movement of the eyes back and forth. ? Strabismus, muscle imbalance of the eyes either crossed or lazy eye. ? Sensitive to bright light and glare. ? People with albinism may be either far-sighted or near-sighted, and often have astigmatism. These eye problems result from abnormal development of the eye because of lack of pigment. 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 a job. Some people do well with bifocals which have a strong reading lens. Others use hand-held magnifiers or special small telescopes. Others use contact lens. Some use bioptics which have small telescopes mounted on or in or behind the regular lenses. In the United States,

people with albinism live normal life spans and have the same types of general medical problems as the rest of the people would. Yet those who live in tropical countries and do not use proper skin protection may develop life-threatening skin cancer. If they use appropriate skin protection, such as sunscreen rated 20 or higher, and opaque clothing, people with albinism can enjoy outdoor activities. People with albinism are at risk of isolation, because the condition and they are often misunderstood. Social stigmatization can occur, especially among communities of color. We should all help by including them in all activities and not discriminate against them. In conclusion the facts on people with albinism are that one in 17,000 people has some type of albinism. Albinism effects