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ALBINISM
vicky s. wang
WHAT IS IT?

Albinism is a defect of melanin production that results in little or
no color (pigment) in the skin, hair, and eyes.


Melanin is a skin pigment (substance that gives the skin its color). Darkskinned people have more melanin than light- skinned people. Melanin
comes in two types: pheomelanin (red) and eumelanin (very dark brown).
Both amount and type are determined by four to six genes which operate
under incomplete dominance
Melanin pigment 
SYMPTOMS?

A person with albinism will have one of the following symptoms:



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Absence of color in the hair, skin, or iris of the eye
Lighter-than-normal skin and hair
Patchy, missing skin color
Albino bunny! 
ALBINO LION
A BRIEF HISTORY

A man in the 17th century named Balthazar Telez, who was an explorer, came
up with the name "Albino", which means white negro, after he saw an albino
African tribe. Balthazar thought he was seeing two different races of people.
This was the first discovery of albinism.

The first ever reported case of albinism that scientifically came up was in
the year 1908. Most of the individuals that have suffered from albinism
have a long history of being ostracized and rebuked by society.
2 MAIN CATEGORIES

Oculocutaneous



involves dilution of the color of the hair, skin and eyes
most common form of albinism
Ocular


melanin pigment mainly missing from the eyes while the skin
and hair appear normal or only slightly lighter
accounts for 10-15% of all albinism cases
TYPES


There are two main types of Oculocutaneous albinism:

Type 1 albinism is caused by defects that affect production of
the pigment, melanin.

Type 2 albinism is due to a defect in the “P gene”. People
with this type have slight coloring at birth.
The most severe form of albinism is called oculocutaneous
albinism. People with this type of albinism have white or
pink hair, skin, and iris color, as well as vision problems.
TYPE 1


Is cause by genetic defect of the tyrosinase enzyme that helps the body to
change the amino acid tyrosine into melanin pigment
OA1 Gene Mutations Associated with Ocular Albinism type 1
TYPE 2



Oculocutaneous albinism type 2 (OCA2) is an recessive
disorder characterized by defective melanin production of
the skin, hair, and eyes, which is caused by mutations of the
"P" gene.
The specific function of P has not been clarified, although it
is likely to act as a transporter in the melanosomal
membrane.
a melanosome is an organelle containing melanin
OCULOCUTANEOUS
2 CATEGORIES
OCULAR
INHERITANCE

Both are inherited in a autosomal recessive
manner

About 1 in 70 people have a gene for albinism.
Couples whom are each carriers of the
recessive albinism gene have a 1 in 4 chance
of producing a child with albinism.
ASSOCIATED PROBLEMS

Skin problems



Easily sunburn
Increased chance of getting skin cancers
Eye problems





Impaired vision: although not blind, vision is impaired and may
not be fully corrected with glasses. Varying degrees of nearsightedness or far-sightedness exist.
Photophobia: sensitivity to light or glare
Nystagmus: involuntary movement of the eyes back and forth
Strabismus: eyes do not fixate and track together
Retinal involvement: this is an important area of the eye as it is
responsible for sending signals to the brain. Impaired
transmission of signals causes various vision disorders
DIAGNOSIS AND TREATMENT




Albinism can be diagnosed by observation of major or total absence of
pigmentation of the appearance of the skin, hair, and eyes.
The most accurate way to determine albinism and its specific type is genetic
testing. This is helpful in families with albinism and is useful for specific,
isolated populations who carry the trait in them.
Recently, a blood test has been developed that can identify carriers of the gene
for some types of albinism.
There is no cure for albinism. Treatment is aimed to ease the symptoms and it
depends on the extent of the disorder. Treatment of the eye conditions
consists of visual rehabilitation.
BIBLIOGRAPHY

Albinism. 15 6 2009. 25 3 2010 <http://dermnetnz.org/colour/albinism.html>.

definition of melanin. 3 26 1998. 24 3 2010
<http://www.medterms.com/script/main/art.asp?articlekey=4340>.

Fawn, Mike. Albinism- A History of Albinism. 25 3 2010
<http://ezinearticles.com/?Albinism---The-History-of-Albinism&id=1362804>.

Saitoh, Shinji. Oculocutaneous albinism type 2 with a P gene missense mutation in a
patient with Angelman syndrome. 25 3 2010
<http://jmg.bmj.com/content/37/5/392.extract>.