Albinism Essay Research Paper The word albinism

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 people

from all races. Most children with albinism are born to parents who have normal

hair and eye color for their backgrounds.


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