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$Unique_ID{BRK03921}
$Pretitle{}
$Title{Leber's Optic Atrophy}
$Subject{Leber's Optic Atrophy Leber's Disease Hereditary Optic
Neuroretinopathy Leber's Optic Neuropathy Retinitis Pigmentosa Macular
Degeneration Flecked Retina Syndrome Oguchi's Disease }
$Volume{}
$Log{}

Copyright (C) 1988, 1989 National Organization for Rare Disorders, Inc.

534:
Leber's Optic Atrophy

** IMPORTANT **
It is possible that the main title of the article (Leber's Optic Atrophy)
is not the name you expected.  Please check the synonym list to find the
alternate names and disorder subdivisions covered by this article.

Synonyms

     Leber's Disease
     Hereditary Optic Neuroretinopathy
     Leber's Optic Neuropathy

Information on the following diseases can be found in the Related
Disorders section of this report:

     Retinitis Pigmentosa
     Macular Degeneration
     Flecked Retina Syndrome
     Oguchi's Disease

General Discussion

**  REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.

Leber's Optic Atrophy is a rare genetic disorder of the eye.  It is
characterized by a slow loss of vision usually beginning around the second
decade, affecting one eye and then spreading to the other.

Symptoms

Leber's Optic Atrophy is noticed as the visual field begins to narrow.  This
disorder usually begins during the second decade of life, and continues with
a progressive loss of vision.  Leber's Optic Atrophy is marked by slow
degeneration of cells in the retina (the part of the eye opposite the pupil).
The involvement of the optic nerve follows causing severely reduced vision or
blindness.  The disorder may mimic glaucoma (an eye disorder caused by high
pressure ) when accompanied by nearsightedness (myopia).  Sometimes heart
abnormalities may also occur.

Causes

Leber's Optic Atrophy is inherited as an autosomal recessive trait.  It is
also suggested that Leber's Disease may be an x-linked recessive trait.

Human traits including the classic genetic diseases, are the product of
the interaction of two genes for that condition, one received from the father
and one from the mother.

In recessive disorders, the condition does not appear unless a person
inherits the same defective gene from each parent.  If one receives one
normal gene and one gene for the disease, the person will be a carrier for
the disease, but usually will show no symptoms.  The risk of transmitting the
disease to the children of a couple, both of whom are carriers for a
recessive disorder, is twenty-five percent.  Fifty percent of their children
will be carriers, but healthy as described above.  Twenty-five percent of
their children will receive both normal genes, one from each parent and will
be genetically normal.

X-linked recessive disorders are conditions which are coded on the X
chromosome.  Females have two X chromosomes, but males have one X chromosome
and one Y chromosome.  Therefore in females, disease traits on the X
chromosome can be masked by the normal gene on the other X chromosome.  Since
males have only one X chromosome, if they inherit a gene for a disease
present on the X, it will be expressed.  Men with X-linked disorders transmit
the gene to all their daughters, who are carriers, but never to their sons.
Women who are carriers of an X-linked disorder have a fifty percent risk of
transmitting the carrier condition to their daughters, and a fifty percent
risk of transmitting the disease to their sons.

Affected Population

Leber's Optic Atrophy can affect both males and females.  However, males tend
to be affected more often than females.

Related Disorders

Symptoms of the following disorders are similar to Leber Optic Atrophy.
Comparisons may be useful for a differential diagnosis:

Retinitis Pigmentosa (RP) is one of a group of inherited vision disorders
causing degeneration of the retina.  Initially this causes reduced vision but
it can progress to blindness.  Retinitis Pigmentosa may also be associated
with other conditions such as deafness (Usher's Syndrome), central nervous
system disorders, metabolic disorders and chromosomal abnormalities.
Difficulty in seeing at night is usually the initial symptom of RP.  Onset of
symptoms usually occurs during young adulthood.  (For more information on
this disorder, choose "RP" as your search term in the Rare Disease Database).

Macular Degeneration is a more common hereditary eye (retinal) disorder
with several subdivisions.  This progressive disorder is characterized by a
gradual loss of vision usually in both eyes.  Symptoms of the various forms
of Macular Degeneration may overlap with those of other degenerative retinal
disorders.  The primary symptoms of macular degeneration include perception
of unclear shapes and blind spots within the field of vision.  (For more
information on this disorder, choose "Macular Degeneration" as your search
term in the Rare Disease Database).

Flecked Retina Syndrome is characterized by reduced vision and impaired
night vision in some cases.  To an ophthalmologist, the area behind the
retinal vessels appears marked with white or yellow flecks.  These flecks are
similar to those found in persons with Leber's Congenital Amaurosis, but the
retina is free from the abnormal markings characteristic of Leber's.  The
macula, retinal and choroidal vessels are usually not affected by this
genetic disorder.

Oguchi's Disease is also known as hereditary night-blindness and may be
associated with vitamin A deficiency.  This nonprogressive disorder occurs
predominately in Japan and usually begins in infancy.  The main symptom is
limited vision in dim light, but patients often have normal color perception
and/or clearness of central vision.  It may take between two and eight hours
for the eyes of affected individuals to adapt to darkness.  The inside back
of the eye appears gray or golden in color when examined by a doctor and the
retinal vessels stand out with clarity.  The optic disk (part of the optic
nerve) is normal.

Therapies:  Standard

Services which benefit the sight-impaired may be helpful to Leber's patients.
Genetic counseling may be of benefit for patients and their families.  Other
treatment is symptomatic and supportive.

Therapies:  Investigational

This disease entry is based upon medical information available through
November 1988.  Since NORD's resources are limited, it is not possible to
keep every entry in the Rare Disease Database completely current and
accurate.  Please check with the agencies listed in the Resources section for
the most current information about this disorder.

Resources

For more information on Leber's Optic Atrophy, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     NIH/National Eye Institute
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

     Eye Research Institute of Retina Foundation
     20 Staniford St.
     Boston, MA  02114
     [phone]

     National Federation of the Blind
     1800 Johnson Street
     Baltimore, MD  21230
     [phone]
     [phone]

     American Council of the Blind, Inc. (ACB)
     1155 - 15th St., NW, Suite 720
     Washington, D.C.  20005
     [phone]
     [phone]

     American Foundation for the Blind (AFB)
     15 W. 16th St.
     New York, NY  10011
     [phone]
     Regional offices:
     Atlanta, GA  [phone]
     Chicago, IL  [phone]
     Dallas, TX  [phone]
     San Francisco, CA  [phone]

     Vision Foundation, Inc.
     818 Mt. Auburn Street
     Watertown, MA  02172
     [phone]
     1-800-852-3029 (Inside Massachusetts)

     American Council of Blind Parents
     6212 W. Franklin Street
     Richmond, VA  23226
     [phone]

     Guiding Eyes for the Blind, Inc.
     611 Granite Springs Rd.
     Yorktown Heights, NY  10598
     [phone]  (Information on Guide Dogs)

     National Association for Parents of the Visually Impaired, Inc.
     P.O. Box 180806
     Austin, TX  78718
     [phone]

     National Association for the Visually Handicapped (NAVH)
     305 East 24th Street
     New York, NY  10010
     [phone]
     or
     3201 Balboa Street
     San Francisco, CA  94121
     [phone]

     National Library Service for the Blind and Physically Handicapped
     Library of Congress
     1291 Taylor Street NW
     Washington, DC  20542
     [phone]

For genetic information and genetic counseling referrals:

     March of Dimes Birth Defects Foundation
     1275 Mamaroneck Avenue
     White Plains, NY  10605
     [phone]

     Alliance of Genetic Support Groups
     35 Wisconsin Circle, Suite 440
     Chevy Chase, MD  20815
     (800) 336-GENE
     [phone]

References

MENDELIAN INHERITANCE IN MAN, 7th ed.:  Victor A. McKusick; Johns Hopkins
University Press, 1986.  Pp. 1411.

LEBER'S HEREDITARY OPTIC NEURORETINOPATHY, A MATERNALLY INHERITED
DISEASE.  A GENEALOGIC STUDY IN FOUR PEDIGREES:  E.K. Nikoskelainen, et al.;
Arch Ophthalmol (May, 1987 issue:  105 (5)).  Pp. 665-671.

THE CLINICAL FINDINGS IN LEBER'S HEREDITARY OPTIC NEURORETINOPATHY.  E.K.
Nikoskelainen, Trans Ophthalmol Soc UK (1985, issue:  104 (Pt 8)).  Pp. 845-
852.

FUNDUS FINDINGS IN LEBER'S HEREDITARY OPTIC NEURORETINOPATHY.  E.K.
Nikoskelainen, et al.; Ophthalmic Paediatr Genet (February, 1985 issue:  5 (1-
2)).  Pp. 125-130.