child with XP wears a NASA designed UV-protective
To the "Children of the Moon,"
nighttime at Camp Sundown is the time to go outside and enjoy
nature. These children suffer from a rare disease that makes
a suntan a potentially fatal experience; their skin is often
damaged so that it resembles that of old people who have spent
too many years in the Sun.
This life-threatening disease is called xeroderma pigmentosum,
XP for short. XP is incurable and very rare; there are fewer
than 1,000 XP patients worldwide. People with XP are extremely
sensitive to ultraviolet light. What makes the disorder so
serious is that any DNA damage from sunlight is irreversible
and accumulates throughout the patient's lifetime.
For most of us, there are ways for the body to repair that
damage. But XP patients are born with a rare genetic defecttheir
bodies are unable to repair damage to DNA from ultraviolet
light. Children with XP are especially prone to skin and eye
cancers. Because of this, they have to avoid known carcinogens
that damage DNA. Regular visits to the doctor are a must,
checking for cancers. Very often, an XP child's first skin
cancer appears before the age of 12.
For an XP patient, just being outdoors can cause severe damage.
In fact, XP sufferers have to take special precautions to
block UV light from entering their homes; they can go out
only at night. Indoors, their houses have to be modified to
block sunlightusing curtains or special UV-absorbing
window films. XP children have to wear protective clothing,
sunscreens, and sunglasses.
Incandescent bulbs cause no harm to XP patients, but bare
fluorescent bulbs may be a hazard. The manufacturer of NASA's
space suits has been exploring the design of a cooled, UV-absorbing
space suit for XP children to wear. The design would be similar
to what the astronauts currently wear, since they are exposed
to high levels of UV when working in space.
The lives of XP patients give us insight into what our world
might be like if the ozone layer in the upper atmosphere were
thinner or even nonexistent. Damage to our DNA would be much
greater, and our repair mechanisms to "fix" DNA
damaged by the Sun would be overwhelmed. We would develop
skin cancers at a much faster rate, and our skin would age
rapidly. Living on other planets that do not have an ozone
layer would also be dangerous, given the ultraviolet light
emitted from the Sun.
the HED Foundation. ©2001 www.hedfoundation.org