Albinism refers to hypopigmentation in the hair, skin, or eyes (in the last case, it’s accompanied by a loss of vision). Its forms vary by the location and amount of pigment loss and are usually rare. The most common type of albinism, which involves moderate but not complete pigment loss, occurs in one out of 15,000 people internationally.
The loss of pigmentation is caused by either (a) melanin production or distribution problems or (b) regeneration problems in melanosomes, the organelles that house melanin. There are a number of genetic mutations that can cause melanin-related abnormalities; each mutation presents with distinct phenotypic features.
Types of Albinism
There are several forms of albinism. The first, Oculocutaneous albinism (OCA) type 1, involves the absence of melanin in the skin, hair, and eyes as well as vision problems. (If you study the word oculocutaneous, this makes sense—both the eyes (oculo) and skin (cutaneous) are affected.) OCA types 2, 3, and 4 are milder forms of OCA type 1: they involve partial, not total, pigment loss in these areas.
Ocular albinism affects melanin production only in the eyes, and presents with visual difficulties.
Chediak-Higashi Syndrome (CHS) involves total or near-total loss of skin, hair, and eye pigmentation, like people with OCA type 1. The difference lies in the quality of a person's hair, which looks metallic; their respiratory problems; and further hypopigmentation in leukocytes, platelets, and reticular cells. This last deficiency manifests as well in another form of albinism, Hermansky-Pudlak Syndrome (HPS).
Griscelli Syndrome (GS), involves mild melanin loss as well as immunological and neurological defects.
Genetics of Albinism
Each type of albinism is caused by genetic mutations. OCA types 1, 2, 3 and 4 are all inherited as autosomal recessive traits (they are not located on sex chromosomes and must be present in both gene copies to be inherited). These four types of OCA result from mutations to the TYR, OCA2, TYRP1, and SLC45A2 genes, respectively. Each of these genes, when expressed normally, functions in the production of melanin. Individuals with mutations to these genes can’t synthesize melanin normally and present with the hypopigmentation characteristic of albinism.
Unlike the four types of OCA, OA is a sex-linked trait, caused by a mutation to the X chromosome. (As a result, OA is more common in males, who only have one X chromosome and thus need only one mutant gene, rather than women’s two.) CHS, HPS, and GS are all autosomal recessive, caused by mutation to the LYST, HPS, and RAB27A genes. LYST affects the Golgi body’s functionality (which is crucial to melanosome production), while HPS and RAB27A affect protein synthesis.
The Bottom Line
All forms of albinism involve a loss of pigmentation. OCA types 1, 2, 3, and 4; CHS; HPS; and GS all are inherited as autosomal recessive traits, while OA is inherited on the X chromosome. Each results from difficulties in synthesizing or distributing melanin.
Is albinism a disability? handicap? neither? or both?
The Americans with Disabilities Act defines disability with respect to an individual as "a physical or mental impairment that substantially limits one or more of the major life activities of such individual; a record of such an impairment; or being regarded as having such an impairment." Albinism involves a visual impairment and in this light can be called a visual disability. A handicap can be defined as "the obstacles a person encounters in the pursuit of goals in real life, no matter what their source." Thus a person with a disability may or may not be handicapped in pursuing the life they want to live."
Albinism itself is not a disability, however characteristics of albinism may be a considered a disability.
Albinism in humans referes to the lack of or limited amounts of pigment produced in the hair, skin, and or eyes.
Sight being one of our five senses and a major dependence for those who have been blessed to have it, can result in loss or reduction of the quality of life and independce if it is loss. So to be born that way may be adaptable but we have to face the fact that there are some things you can not do with out your sight. Driving is one of those major life things. Although technology is rapidly reducing that disadvantage for persons with low vision, there are others who can not benefit from that technology.
The visual impairment associated with albinism due to lack of pigment developing in the eyes are: difficulty seeing at a distance. With the vision being distorted as a result of the lens not being able to reflect the light projected through the iris. Since the pigment would produce the opaque color needed to reflect the light it would be impossible to for the eye to cast a clear image. Always resulting in some sort of distortion of what we are able to see. I think that can affect the quality of ones life and could be considered a disability on those terms.
A disability is a handicap and they are one in the same. Lables mean only what we interput them as. Because albinism is generally accompanied by a visual impairment it can be considered a disability, because with out albinism it is possible that one could have 20/10 vision, but with it, research indicates 20/50 is the best vision possible and that is with correction. Since an individual with much better vision may be able to easily still do many more things than someone with less vision that is why albinism is considered a disability on a case by case basis.
The primary disability is the vision impairment and the serverity of it makes a differnce. Legal blindness is classified at 20/200, so any better vision doesn't count.
So my final answer is Albinism "can" be used as an apparent determination of a disability due to the visual impairment that is associate with the condition which results little to no pigment developing in the "eyes".(Nystagmus is an added diddy that reduces the ability to focus even more, it to is recognized as an albinism trait and determining factor of the condition.)
Rae Lowery
Vice President
The Albinism Alliance Group
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