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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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