Huntington's disease, also known as Huntington's chorea is a genetic
disorder that usually shows up in someone in their thirties and forties,
destroys the mind and body and leads to insanity and death within ten to
twenty years. The disease works by degenerating the ganglia (a pair of nerve
clusters deep in the brain that controls movement, thought, perception, and
memory) and cortex by using energy incorrectly. The brain will starve the
neurons (brain cells), and sometimes make them work harder than usual,
causing extreme mental stress. The result is jerky, random, uncontrollable,
rapid movement such as grimacing of the face, flailing of arms and legs, and
other such movement. This is known as chorea.
Huntington's chorea is hereditary and is caused by a recently discovered
abnormal gene, IT15. IT stands for "interesting transcript" because of the
fact that researchers have no idea what the gene does in the body.
Huntington's disease is an inherited mutation that produces extra copies of
a gene sequence (IT15) on the short arm of chromosome 4. A genetic base that
exists in triplicate, CAG for short, is effected by Huntington's disease. In
normal people, the gene has eleven to thirty-four of these, but, in a victim
of Huntington's disease the gene exists from anywhere between thirty-five to
one-hundred or more. The gene for the disease is dominant, giving children
of victims of Huntington's disease a 50% chance of obtaining the disease.
Several other symptoms of the disease exist other than chorea. High levels
of lactic acid have been detected in patients of Huntington's disease as a
bi-product of the brain cells working too hard. Also, up to six times above
the normal level of an important brain brain protein, bFGF (or basic
fibroblast growth factor) in areas of the brain effected by the chorea. This
occurs from the problems on chromosome 4, where the gene for control of bFGF
is also located.
As of yet, there is no treatment for Huntington's disease. But with the
discovery of the mutated genes that cause it, there is now a way of
diagnosing if you will get it. This technique was discovered only recently
and reported in the Journal of American Medical Association in April, 1993.
Something that many people do not want to know. Because it can go two ways.
Either you are extremely relieved because the test shows up negative, and a
great burdon is lifted off of your mind, or you show up positive, and know
how and a little bit about when you will die, increasing the burdun very
greatly. And living the rest of your life in depression.
Some 30,000 Americans are currently suffering for this genetic disorder.
Named in 1872 for George Huntington the New York Doctor who first wrote down
it's devestating symtoms, Huntingtons disease up to now was a silent time
bomb.
13,000 people, the largest known concentration of sufferers from
Huntington's Disease, live in the Lake Maracaibo region of Venezuela. The
origins of this gene pool has been traced back to the 1800's to a woman
named Maria Concepcion. It was from blood samples of these people that
scientists became extraordinarily lucky and isolated the genetic marker that
shows the presence of this disorder. Today, it is believed that Maria
obtained the disease when she was birthed by a european sailor.
Since it was first recorded by George Huntington, a Long Island doctor,
Huntington's disease had remained fairly low key. No one heard about it
until it infected Woodie Guthrie, A famous folk singer from the 1920's who
showed symptoms of the disease. In 1967, he died. This put Huntington's
Disease on the map, but it still was not well known. But, before Woodie
guthrie died, he had a son, Arlo Guthrie. He, too became a famous folk
singer, this time from the Seventies. He became extremely famous, but had to
live with the fact that he has a 50% chance of having the disorder. That
aroused huge public interest and made the disease well-known.
Now that you know about Huntington's disease, you can imagine how it works,
and the probability of getting it. But, can you imagine how it feels to have
the disorder? What would it be like to know that you have a 50% chance of
not reaching your sixtieth birthday? Now, enter the life of Nancy Wexler, a
woman who knows how it feels for both of these. She watched as her mother
died from the disease, and has to live with the fact that she may be next.
When Wexler was young, three of her uncles died of the killer disease. "Men
only got Huntington's disease" went the myth. Then it happened; her sister
was told by her doctor that her unusual walk was an early symptom. She too
had the disease. Since then, she and her sister Alice, swore never to have
children. Years later, Wexler joined up with her husband Milton Wexler, and Marjorie
Guthrie, wife of Woodie Guthrie, and formed the Los Angeles chapter of the
Commitee to combat Huntington's Disease. Guthrie wanted to focus the
organization on patient care, but Wexler was intent on finding a cure. So,
she began to invite biologists to help study the disease while she worked to
get her Ph.D. In 1976 she moved to Washington to become executive director
of the Congressional Commission for the control of Huntington's disease and
it's Consequences.
Once there, they discovered that Huntington's disease works by distroying
the Ganglia. Then they decided that the best way to research Huntington's
disease was at the level of the gene. They decided to loook for a "marker"
(small identifiable piece of DNA) of where the faulty gene is located. This
normally would yave taken 50 to 75 years to find. But, on a freak chance,
they found it. it was the 12th marker that they tested. The discovery of the
marker led to the discovery of the gene which won Wexler the Albert Lasker
Public Service Award. The highest honor in American medicine. She also
developed a test to accurately determine whether or not someone will get
Huntington's disease.
Wexler will not reveal if she, herself has taken the test because she does a
multitude of genetic counciling, and does not want to sway her patients'
decisions on whether or not to take the test. But, whether she tests
positive or negative, Huntington's disease will live on. Unless scientists
like Wexler can find a cure.
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