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Albinos: Scientific explanation, causes and tragic consequences
2008-03-30 09:29:29
By Dr Simeon Mesaki
According to Prof. William Oetting of the Department of Medicine-Genetics at the University of Minnesota, albinism has been in ``literature`` since the beginning of medical literature.
He refers to several Greek and Roman authors (Plinius Secundus and Aulus Gellius for example) that have described albinism in man, adding that the first accurate scientific paper written about albinism was by Sir Archibald Garrod in 1908.
ALBINISM IN HUMAN
Albinism is found in humans of all races although it is most startling when they occur in dark-skinned people. Albinism is also found in the lower animals, and is exemplified ordinarily by rats, mice, crows, robins, etc.
In the Natural History Museum in London there are stuffed examples of albinism in the lower animals. In Tanzania an ``albino`` giraffe was spotted by Charles Foley in 2005.
Albino is derived from a Latin word ``albus``. The word ``albinism`` refers to a group of inherited conditions.
Albinism is characterized by the absolute or relative absence of pigment of the skin, due to an arrest, insufficiency, or retardation of this pigment.
People with albinism have little or no pigment in their eyes, skin, or hair. They have inherited altered genes that do not make the usual amounts of a pigment called melanin.
Because of the lack of melanin, their skin is oversensitive to sunlight and skin disorders. They are therefore prone to skin cancers.
ORDINARY TYPE OF ALBINO
They also suffer from short-sightedness. A description of the ordinary type of albino would be as follows: The skin and hair are deprived of pigment; the eyebrows and eyelashes are of a brilliant white or are yellowish; the iris and the choroids are nearly or entirely deprived of colouring material; from absence of pigment they necessarily keep their eves three-quarters closed and are photophobic to a high degree.
TYPES OF ALBINISM
The literature I have consulted distinguishes the following types of albinism:
While most people with albinism have very light skin and hair, not all do.
Oculocutaneous (pronounced ock-you-low-kew-TAIN-ee-us) albinism (OCA) involves the eyes, hair and skin. Ocular albinism (OA), which is much less common, involves primarily the eyes, while skin and hair may appear similar or slightly lighter than that of other family members.
Oculocutaneous albinism type 1 (OCA1 or tyrosinase-related albinism) results from a genetic defect in an enzyme called tyrosinase (hence `ty` above). This enzyme helps the body to change the amino acid tyrosine into pigment. (An amino acid is a ``building block`` of protein.)
Oculocutaneous albinism type 2 (OCA2 or P gene albinism) results from a genetic defect in the P protein that helps the tyrosinase enzyme to function. Individuals with OCA2 make a minimal amount of melanin pigment and can have hair colour ranging from very light to brown.
Oculocutaneous albinism type 3 (OCA3) results from a genetic defect in TYRP1, a protein related to tyrosinase. Individuals with OCA3 can have substantial pigment.
Oculocutaneous albinism type 4 (OCA4) is caused by a genetic defect in the SLC45A2 protein that helps the tyrosinase enzyme to function. Individuals with OCA4 make a minimal amount of melanin pigment similar to persons with OCA2.
ASPECTS OF ALBINISM A DISABILITY?
People with albinism in African countries have a very different life situation than people with albinism from countries where the majority of the population is white. In western countries people with albinism do not stand out as much as they do in countries where the majority of the population is black.
In many African countries albinism is considered a disability, and people with albinism often consider themselves to be disabled. Social attitudes toward albinism are often similar to those experienced by other disability and minority groups. These attitudes include a lack of understanding, fear and prejudice based on appearance.
APPEARANCE
The most conspicuous aspect of albinism which most people notice is the person’s unusual appearance. The white hair and skin of oculocutaneous albinism is a powerful factor from the moment of birth. The new baby will often be much lighter in colour than any family member.
This colouring with albinism is a dramatic contrast to the family and community.
Strangers will often make unwanted and unkind comments about the appearance and possible causes. Albinism, especially in Africa, is shrouded in mystery, misinterpretation and in many cases infanticide was/is common (subsequent articles).
VISION PROBLEMS
People with albinism always have problems with vision (not correctable with eyeglasses) and many have low vision. Vision problems in albinism result from abnormal development of the retina and abnormal patterns of nerve connections between the eye and the brain. It is the presence of these eye problems that defines the diagnosis of albinism. Thus the main test for albinism is simply an eye examination.
SKIN PROBLEMS
People with many types of albinism need to take precautions to avoid damage to the skin caused by the sun such as wearing sunscreen lotions, hats and sun-protective clothing.
Language, Myth and Stereotypes Language can shape ideas and create reality. There are many words, both in the local languages and in English, that are used to describe a person with albinism.
The most common name in Kiswahili speaking areas is ``Mzungu``, this being kind of mockery name. Teasing and name-calling are common in referring to albinos. In Tanzania the word is Zeru Zeru (ghost) or mzungu. Albinos are called ``sope`` in Zimbabwe.
In Malawi people with albinism are often referred to as `yellow man` or ``Zigoma, after Jeffrey Zigoma a famous gospel singer in the country who is an albino. Another name of albinism in Malawi is ``napwere``-that is, dry pigeon peas, for when they are dry they are kind of brownish.
In the next series of articles on albinos we shall look at the prevalence of albinism in some African countries, some prominent people who have proved that being an albino does not mean lower intelligence and attitudes, beliefs, myths, superstitions on the causes and consequences of being an albino in Africa with reference to Tanzania.
Dr Simeon Mesaki is a renowned sociologist-cum-anthropologist who has done tremendous research on the subject of witchcraft.
0713 407 625
mesakis@yahoo.com
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