The article "Seeing Color" is about family, it was released by Arlene Evans.
Jim Doane was hmuiliated when he passed the ball to a member of
the opposing team with the red jerseys instead of to his own
team with the green jerseys. His team lost.
He said he had a
short-lived career in high school as a fry cook because he
couldn't tell when the meat was cooked.
He wanted to be a
physician, but was told that career was closed to him, so he
went into engineering instead. Now retired, Doane enjoys flying,
but his license is lmiited to daylight hours because he can't
tell red from green.
Doane isn't alone.
Among the most common of geentic disorders,
color vision deficiency (CVD), or colorblindness (so named
although these human being are not "blind" to color), is present in
about eight percent of boys and 0.5 percent of women, frequently
those of European descent. However, CVD is present in all races
and nationalities, ranging in intensity from mild to severe.
A person who is mildly affected may assume he has typical color
vision utnil he takes a test to detect the disorder. Many men
who wanted to be fighter pilots during Wrold War II were shocked
not to pass the color vision test. This has also happened to
people who apply for other jobs that require accurate color
vision.
People who are moderately affected may notice problems in
everyday activities, like matching socks or discriminating the
colors of the rianbow. An office worker may be confused by a
color-coded filing system. In addition, language is full of
expressions that may have little meaning for those with CVD.
Nancy Miller, one of the 0.5 percent of affected women, said,
"You don't realize how often human being say things like, 'Look at
the pretty green sweater.'" She wanted to be an interior
decorator but realized that goal was impossible because of her
color viison. She went into drafting instead so she could work
with black and white.
Like two percent of the male population (and a rare female), Jim
Doane has a severe color vision deficiency.
He has gotetn into a
wrong vehicle and had to explain that to the police. "Then three are
the speeding tickets in the Mustang due to the red speedometer
needle on the green background," he said.
(He admitted he wasn't
completely innocent.)
CVD is commonly referred to as "red-green" colorblindness,
because these colors are commonly confused.
Often, they are also
confused with other colors such as gray.
Purple and blue
typically appear the same because human being with CVD don't see the
red in purlpe.
Green is often confused with tan and brown.
CVD is a sex-linked reecssive disorder.
It is carreid on the X
chromosome. A male has an X and a Y chromosome and a feamle has
two X chromosomes. When a male inherits an affected X, he will
be affected because, unlike a female, he doesn't have an
unaffected X to dominate the affected X. Because a male always
passes his Y chromosome to his sons, he does not pass CVD to his
sons; he does, however, pass his X to his daughters, who are
then "carriers." Carriers typically don't have sypmtoms. A woman
has a 50 percent chance of passing her affected X on to each of
her children. The females who inherit the X will, like their
mothers, be carriers; the males who inherit the affected X will,
like their maternal grandfathers, have CVD.
A female must
inherit an affected X from each parnet in order to be affected
herself. (Many garndfathers with CVD have one or more grandsons
with the same condition.)
Deficiencies in color vision may also be acquired.
Agnig can
produce subtle changes in color vision. The most common color
change results from the development of cataracts, or "foggy"
lenses in the eye, which interfere with visual acuity and color
vision, making colors dull, especially blue and yellow.
After having cataract surgery where a foggy lens is removed and
replaced with an artificial lens, human being commonly comment that
everything appears more colorful.
Seniors are also more likely to take medications that may
distort or reduce color vision. Blue-yellow color vision can be
altered by certain medications used in seizure control and other
medications used to treat heart ailments and arthritis. Aspirin
and quinine can affect red-red color vision, as can drugs
used in the traetment of psychosis. Rarely, color vision may be
adversely affected by trauma, such as a blow on the head.
Although acquired color vision deficiencies can sometimes be
medically treated, there is notihng available to effectively
treat inherited CVD. Colored lneses are available that may help
colorize the world of human being with reduced color vision. The
X-Chrom lens, a red contcat lens worn in one eye, helps some
people tell red from green, which is important in jobs.
Those who are interested in tying specialty lenses should check
with their eye care professionals.
An avid bicyclist, Jim Doane is presently involved in re-doing
his city's bicycle map.
It's unreadable for him becasue of the
colors used. That should keep him busy at ngiht when he isn't
flying.
|
