- Jul 29, 2012
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http://www.nytimes.com/1981/09/15/science/in-albino-studies-scientists-search-for-pigment-error.html
MINNEAPOLIS BORN with a defective ability to form pigment, albinos are conspicuous people. Their whitish hair and skin and pale, squinting eyes often cause them to suffer more from social stigma than from their actual physical disabilities.
In the hope of someday allaying the social and physical handicaps of albinos, scientists at the University of Minnesota are unraveling the intricacies of pigment formation, looking for an understanding that may help them correct the genetic flaws that cause the disorder.
These defects afflict about one in 20,000 Americans, with the frequency higher in blacks than in whites. In all albinos, there is an absence or shortage of melanin, the pigment in skin that protects underlying cells and blood vessels from damage by ultraviolet radiation.
To add to their burdens, albinos are usually cross-eyed and myopic, and suffer from nystagmus, an uncontrolled movement of the eyeball. But though they have poor eyesight, contrary to popular impressions, they are neither blind nor ******ed. In fact, studies at the University of Minnesota have shown that, if anything, albinos tend to be ''overachievers,'' with intellectual accomplishments that surpass expectations based on tests of intellectual ability.
''Because of their visual handicaps, they can't play ball, ride bikes or watch television,'' said Dr. Richard King, a geneticist at the university, which operates the world's only clinic exclusively devoted to studying the causes and treatment of albinism. ''But they can see up close to read, so many overcompensate by becoming studious. We have albinos here who are in medical school, law school and graduate school.'' Albinism is nearly always inherited as a re cessive characteristic, which means that to become an albino a child has to inherit the same gene for albinism from each parent. A parent who carries a single albino gene would appear normal. When both pa rents are carriers for the same albino gene, each of their children has one chance in four of being an albino and one chance in two of b eing a carrier of the abnormal gene.
In this country, albinos have a normal life expectancy. But in Nigeria, where one in 1,100 is born an albino, these light-skinned people are subject to life-threatening skin cancers from exposure to the tropical sun. In cooperative studies with Nigerian physicians, the Minnesota researchers, headed by Dr. Carl Witkop, found that half the Ibo albinos, who live in what used to be Biafra, developed cancer by the age of 26 and none lived beyond 40.
While human albinos are often subject to jeers, albino animals - such as the white tiger, Himalayan rabbit and Siamese cat - are prized for their unusual coloring. Albino animals also tend to be docile and are preferred subjects in laboratory research.
The studies of albino humans at the University of Minnesota call into question the many animal experiments that have used albino mice and rats to explore learning theory and to test reactions to drugs and alcohol. Dr. King noted that the visual problems would impair performance on learning tests and albino animals do not respond to alcohol and drugs the way pigmented animals do.
The visual problems of albinos have been traced to the fact that their optic nerve fibers do not cross properly in the brain and many end up connected to the wrong side of the brain. Normally, some fibers cross to the opposite side of the brain, and the rest connect to the same side of the brain as the eye from which they emerge.
The albino pattern of a very large proportion of crossed fibers is typical of lower animals, like most birds and reptiles, that have eyes on the sides of their heads and panoramic vision rather than the forward-facing eyes and binocular vision typical of mammals. In effect, each side o f the brain only ''knows'' about the visual input from one eye, and so cannot properly integrate the two images to produce a bin ocular picture. Patterns Are Discovered
The eye tract patterns were deciphered by Dr. R. W. Guillery, a neurophysiologist at the University of Chicago, who has worked extensively with Siamese cats. These cats typically have blue eyes and are colored only at the outer reaches of their bodies -ears, tail, nose and paws. In the Siamese cat, the enzyme responsible for pigment formation is heat-sensitive, working only at the cooler extremities.
The optic tract abnormalities apparently result from a lack of pigment in crucial nerve cells during fetal development, Dr. King said. The Minnesota researchers recently showed that auditory pathways also develop abnormally probably because pigment is lacking in the inner ear.
Studying people with different hair colors, Dr. King and others have mapped out the biochemical pathway by which pigments form. And they have shown that at least 14 different defects can occur in this pathway to result in albinism.
Pigment formation begins with an amino acid called tyrosine, which is converted by the enzyme tyrosinase into other chemicals that ultimately form red-yellow or brown-black pigments. In some albinos, a complete absence of pigment results from a lack of tyrosinase. But in others less severely affected, the enzyme is present and the defect occurs further down in the pigment-forming pathway.
John Brumbaugh, a visiting scientist from the University of Nebraska, has taken the cells from albinos with different pigment defects, combined them in a test tube and shown that sometimes they compensate for each other's abnormality. According to Dr. Witkop, ''Biochemically, we can correct some defects in the test tube. We hope to determine if these methods can be used in the living person.''
In addition to helping albinos, Dr. King said the studies of how pigmentation occurs and how the process can go wrong may help in the diagnosis and treatment of other pigment disorders, including melanoma (pigmented skin cancer) and Addison's disease, an adrenal disorder in which the skin darkens.
In response to what I said about sickle cell, you took what I said out of context yet more or less still made my point for me. Your melanin is always going to create a biological response to outside threats. So yes it did come about in the way you mentioned, but how many Black people in America do you see exposed to Malaria still? And before you even say that it's genetic, how is a biomechanism intelligent enough to manipulate the celluar structure to prevent disease, but then not intelligent enough to restructure itself once the mechanism becomes self destructive? I'm sure you know this but cancer has consistently rose over the years, what's your justification for that?
Here's a good book to check out just in case you wanna understand how melanin works beyond the epidermis.
So where are my random myths? Just cause you haven't put in the leg work don't underestimate the knowledge of those who have. And be realistic, it's been proven time and time again that the "powers to be" are waging war on the black family unit. It's not going to be easy at times to just google search things that would undermine a global structure of white supremacy. (No im not suggesting people just pull anything out of the air and act like its the gospel)
and to address your earlier statement about all the successful business men you know, say every black man in the world followed that plan and worked themselves into a position where everyone is a millionaire and wanted for nothing materialistically.... then what?
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learning a lot more. Need to find a focal point and expand to learn more though. So much to learn, I might start w/ religion and the whole concept of God and Jesus, it always struck me as odd that European people were praising a man from Africa, has to be more to it.
