This document discusses albinism, a congenital disorder characterized by little or no pigmentation in the skin, hair and eyes. It is caused by a recessive gene that results in a lack of the enzyme tyrosinase needed to produce melanin. There are different types of albinism that can affect the eyes only or eyes, skin and hair. Albinism is associated with vision defects like photophobia, nystagmus and astigmatism as well as sun sensitivity. Diagnosis involves genetic testing or eye exams. Treatment focuses on protecting the skin from sun exposure and addressing vision problems. The condition does not affect lifespan except in rare cases of associated disorders.
2. called achromia,
achromasia, or achromatosis
is a congenital disorder
characterized by the
complete or partial absence
of pigment in the skin, hair
and eyes due to absence or
defect of tyrosinase, a
copper-containing enzyme
involved in the production of
melanin
3. Albinism results from inheritance of recessive gene alleles and
is known to affect all vertebrates, including humans.
ALBINO- organism with complete absence of melanin
ALBINOID- an organism with only a diminished amount of
melanin
Albinism is associated with a number of vision defects, such as
photophobia, nystagmus and astigmatism. Lack of skin
pigmentation makes for more susceptibility to sunburn and
skin cancers.
4. Oculocutaneous
affecting the eyes, skin and hair
people with this type of albinism have white or pink
hair, skin, and iris color, as well as vision problems.
most severe type
Ocular
affecting the eyes only.
person's skin and eye colors are usually in the normal range.
However, an eye exam will show that there is no coloring in
the back of the eye (retina).
5. Hermansky-Pudlak syndrome (HPS)
is a form of albinism caused by a single gene. It can occur
with a bleeding disorder, as well as with lung and bowel
diseases.
causes scarring of the lungs, or fibrosis, creating breathing
difficulty and fatigue and leading to lung disease.
HPS interferes with platelet formation, making it difficult
for cuts and wounds to heal. Many albinos bruise easily,
have frequent nosebleeds, and or experience gum bleeding
while brushing their teeth. HPS in women causes excessive
bleeding during labor and monthly menstrual cycles.
6. Chediak-Higashi Syndrome
of coloring all over the skin, but not complete
Tuberous Sclerosis
small areas without skin coloring
Waardenburg Syndrome
often a lock of hair that grows on the forehead, or no
coloring in one or both irises
7. A person with albinism will have one of the
following symptoms:
Absence of color in the hair, skin, or iris of the eye
Lighter than normal skin and hair
Patchy
Many forms of albinism are associated with the
following symptoms:
Crossed eyes (strabismus)
Light sensitivity (photophobia)
Rapid eye movements (nystagmus)
Vision problems, or functional blindness
8. Genetic testing
Electroretinogram test
Reduce sunburn risk by avoiding the sun, using sunscreen, and
covering up completely with clothing when exposed to the sun.
Sunscreen should have a high sun protection factor (SPF).
Sunglasses (UV protected) may relieve light sensitivity.
Glasses are often prescribed to correct vision problems and eye
position. Eye muscle surgery is sometimes recommended to
correct abnormal eye movements (nystagmus).
9. Albinismdoes not usually affect lifespan.
Hermansky-Pudlak syndrome can, however,
shorten lifespan due to lung disease or
bleeding problems.
People with albinism may be limited in their
activities because they can't tolerate the
sun.