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Ocular albinism in an inherited condition in which the eyes lack
melanin pigment, while the skin and hair show normal or near-normal
The lack of pigment in the eyes causes various vision problems:
Reduced visual acuity from 20/60 to 20/400 and sometimes as good as
20/25 in African-Americans, Nystagmus - involuntary back-and-forth
movement of the eyes, Strabismus - crossed eyes or "lazy" eye, and
Sensitivity to bright light and glare.
The reduced visual acuity may result in difficulty in school, such as
inability to read what is written on a chalkboard except when very
close, and difficulty with ball sports. It may also result in inability
With ocular albinism, the color of the iris of the eye may vary from
blue to green or even brown, and sometimes darkens with age. However,
when an eye doctor examines the eye by shining a light from the side of
the eye, the light shines back through the iris since very little
pigment is present. There may be areas of the iris which have very
The main problem with the eye in ocular albinism is in the fovea, small
area of the retina which affords acute vision. With ocular albinism,
the fovea does not develop completely, presumably because melanin
pigment is needed for the growth processes that normally occur before
birth. Therefore the eye cannot process sharp light images. Because the
fovea does not develop well, it is difficult to correct vision
completely with glasses.
Another defect in ocular albinism is that nerves from the back of the
eye to the brain do not follow the usually pattern of routing. From the
normal eye, nerve fibers go to both sides of the brain, that is, the
same side as the eye and the side opposite from the eye.
From the eye with ocular albinism, more of the nerve fibers cross from
the eye to the opposite side of the brain. A test called a visually
evoked potential, which is performed like an EEG or brain wave test,
can show this difference. These eye problems are very similar to those
of oculocutaneous albinism (albinism which involves the skin and hair
as well as the eye).
In most cases ocular albinism is X-linked, which means the gene for it
is on the X chromosome. X-linked ocular albinism occurs almost
exclusively in males. It is passed from mothers who carry the gene to
their sons. Each time a mother who carries the gene for ocular albinism
gives birth to a son, there
is a 1 in 2 chance that the son will have ocular albinism. Mothers who
carry the gene may have mottled pigmentation in the back of their eyes,
but do not have the full syndrome of ocular albinism.
An ophthalmologist may be able to identify this mottling in about 80%
of cases. X-linked ocular albinism is also called Nettleship-Falls
A less common type of ocular albinism shows a different pattern of
inheritance, autosomal recessive. With this type of inheritance, both
parents of a child with autosomal recessive ocular albinism carry the
gene for it. Boys and girls are equally affected. If both mother and
father carry the gene, then at each birth there is a one in four chance
that the child will have ocular albinism. Newer research suggests that
autosomal recessive ocular albinism is a variant of oculocutaneous
albinism. The skin and hair color may be somewhat lighter than that of
other family members.
Autosomal recessive ocular albinism may be a variant of either
tyrosinase-related (type 1) or P gene (type 2) oculocutaneous albinism
(see Information Bulletin, What is Albinism?).
Testing for the Ocular Albinism Gene
Researchers have identified some, but not all of the DNA defects in
ocular albinism. Therefore blood tests to identify genes for various
types of albinism are not conclusive enough to be used for genetic
Most of the time an ophthalmologist can identify a carrier of the
X-linked albinism gene by seeing mottling of pigment in her retinas. If
this mottling is not apparent, research labs can examine a hair bulb or
skin biopsy from a child. This will show unusually large granules of
pigment in X-linked ocular albinism, but not in autosomal recessive
Those with questions about their own situation and inheritance of
ocular albinism should seek a genetic counselor. Many parents of
children with ocular albinism decide to have more children. These
parents find their children can function well despite their visual
disabilities if they are provided with appropriate support and
Treatment of ocular albinism includes using visual aids and
environmental changes to expand the limits of vision. Surgery for
strabismus is sometimes helpful, but usually does not result in fine
coordination of the eyes. Surgery can improve the field of vision if
the eyes are crossed, and may improve appearance and the child's self
The choice of optical aids for a child or adult is an individual one.
Some children may do well with ordinary glasses. For older children and
adults, glasses with small telescopes mounted on the lenses may help
with both close and distant vision.
Contact lenses sometimes provide additional correction that glasses
Also important in the treatment of ocular albinism is attention to
emotional and social adjustment. Often parents and people with ocular
albinism feel anger and shame about the condition and try to deny it or
pretend it does not exist.
This denial can result in the person with albinism experiencing low
self esteem, difficulties in relationships with others, and low
functioning in school and work.
It is important for parents of a child with ocular albinism to learn as
much as possible about the condition. and about low vision. Parents
must be open and honest with the child, family members, friends, and
others about the child's low vision and the reason for it. (See also
the NOAH Information
Bulletin "Social and Emotional Aspects of Albinism.")
Participation in support groups such as NOAH and NAPVI (National
Association of Parents of Visually Impaired) can help in gathering
information as well as in dealing with feelings about the condition.
Children and adults with ocular albinism can benefit from participation
in peer support groups such as NOAH and Council of Citizens with Low
These groups can help the individual to feel less isolated, to learn
positive attitudes and coping skills from others with low vision, and
to gather valuable resource information.
NOAH can provide other information bulletins on visual aids, assisting
students with albinism in the classroom, and resources for social and
More technical information for health professionals on ocular albinism
can be found in:
The National Organization for Albinism and Hypopigmentation
PO Box 959, East Hampstead, NH 03826-0959
Phone: 800 473-2310 (US and Canada)
Phone: 603 887-2310 Fax: 800-648-2310
NOAH is a volunteer organization for persons and families involved with
the condition of albinism. It does not diagnose, treat, or provide
genetic counseling. It is involved in self-help, while trying to
promote research and education.
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