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$Unique_ID{BRK03503}
$Pretitle{}
$Title{Ataxia, Friedrich's}
$Subject{Ataxia, Friedrich's Familial Ataxia Friedreich's Disease Friedreich's
Tabes Hereditary Ataxia Spinocerebellar Ataxia Spinal Ataxia, hereditofamilial
Marie's Ataxia Charcot-Marie-Tooth Disease Ataxia Telangiectasia
Olivopontocerebellar Atrophy Scoliosis}
$Volume{}
$Log{}

Copyright (C) 1984, 1987, 1988, 1989, 1992 National Organization for Rare
Disorders, Inc.

7:
Ataxia, Friedrich's

** IMPORTANT **
It is possible the main title of the article (Friedrich's Ataxia) is not
the name you expected.  Please check the SYNONYMS listing on the next page to
find alternate names and disorder subdivisions covered by this article.

Synonyms

     Familial Ataxia
     Friedreich's Disease
     Friedreich's Tabes
     Hereditary Ataxia
     Spinocerebellar Ataxia
     Spinal Ataxia, hereditofamilial

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

     Marie's Ataxia
     Charcot-Marie-Tooth Disease
     Ataxia Telangiectasia
     Olivopontocerebellar Atrophy
     Scoliosis

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.


Friedreich's ataxia is a progressive, hereditary neuromuscular syndrome
that generally becomes apparent in childhood or adolescence.  Slow
deterioration (degenerative changes) of the spinal chord and brain occur.
These degenerative changes affect speech and movement (motor coordination)
producing numbness or weakness of the arms and legs, curvature of the spine
(secondary lateral scoliosis), and lower limb paralysis.  Although the
disorder is progressive and treatment is symptomatic, unexplained sudden
(spontaneous) remissions of 5 to 10 years in duration have been reported.

Symptoms

The primary symptom of Friedreich's Ataxia is progressive weakness of the
legs, which may appear as a staggering, lurching way of walking (gait), or
trembling when the patient is standing still.  Ataxia is defined as a failure
of muscle coordination that generally results in an unsteady gait.  Partial
loss of the sense of touch or sensitivity to pain and temperature may also
occur.  With time, reflexes in the legs may slow or be absent, and a high-
arched foot may develop with overextension (hyperextension) of the big toe.
Involvement of the throat muscles may lead to impaired swallowing and choking
and may cause difficulty in eating.  The intellect and emotions are rarely
affected.  Lateral or sideways curvature of the spine (scoliosis), diabetes
mellitus, or degenerative changes in the heart (cardiomyopathy) may occur but
are not necessary for a differential diagnosis.

Symptoms of Friedreich's Ataxia are caused by the gradual deterioration
(degeneration) of nerve cells on the back portion of the spinal nerves (the
dorsal ganglia), spinal cord and brain.

Causes

Friedreich's Ataxia is usually inherited as a recessive genetic trait.
Another form may be inherited as a dominant 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.

In dominant disorders, a single copy of the disease gene (received from
either the mother or father) will be expressed "dominating" the normal gene
and resulting in appearance of the disease.  The risk of transmitting the
disorder from affected parent to offspring is 50% for each pregnancy
regardless of the sex of the resulting child.)

During 1988 scientists located a genetic marker for Friedreich's Ataxia
which is located on chromosome 9 (proposed on the proximal short arm,
location 9p22).   The marker pinpoints the location on the chromosome where
the defective gene is located.  Once the exact gene is cloned, scientists
hope to identify the defective protein and understand how it causes
Friedreich's Ataxia.  New treatments may then be developed to alter
progression of the disease, and genetic tests will more readily identify
carriers of the gene.

Affected Population

Although Friedreich's Ataxia can be present at birth, symptoms usually first
appear between the ages of 8 and 15 years.  Estimates of occurrence in the
United States range from 2,000 or 3,000 cases to as many as 20,000.  A more
precise estimate is difficult to arrive at as many cases are likely the
result of misdiagnosis.  Friedreich's Ataxia is the most common of the
various forms of hereditary ataxias.

Related Disorders

Symptoms of the following disorders can be similar to those of Friedreich
Ataxia.  Comparisons may be useful for differential diagnosis.

Ataxia is a group of disorders which are characterized by an unsteady
gait caused by the failure of muscular coordination.  There are many forms of
Ataxia.  Some ataxias are hereditary, some have other causes, and sometimes
ataxia can be a symptom of other disorders.  (To locate information about
other types of ataxia choose "Ataxia" as your search term in the Rare Disease
Database.)

Marie's Ataxia is a hereditary disorder that affects the brain
(cerebellum) and causes a lack of muscle coordination.  The first symptom is
usually an unsteady walk or gait.  Progressive degeneration of spinal nerves
leads to tremors and a wasting (atrophy) of the muscles in the arms, legs,
head and neck.  Marie's Ataxia can appear in either early adulthood or in
middle age.  The symptoms of Marie's Ataxia may include abnormal reflexes,
muscle contractions, and a decrease in perception of pain or touch.  (For
more information on this disorder, choose "Marie's Ataxia" as your search
term in the Rare Disease Database).

Charcot-Marie-Tooth Disease (also known as CMT Disease) is a hereditary
neurological disorder characterized by weakness and atrophy, primarily in the
muscles of the legs.  Symptoms of Type I Charcot-Marie-Tooth Disease usually
begin in middle childhood or teenage years with a deformity of the foot
characterized by a high arch and hyperextension of the toes (gampsodactyl or
claw-foot).  This produces a "stork leg" deformity.  With time, Charcot-
Marie-Tooth disease spreads to the upper extremities and produces a
"stocking-glove" pattern of diminished sensitivity.  There is a decrease in
the sensitivity to vibration, pain and temperature.   (For more information
on this disorder, choose "Charcot-Marie-Tooth Disease " as your search term
in the Rare Disease Database).

Ataxia Telangiectasia, also known as Louis-Bar Syndrome, is an inherited
progressive cerebellar ataxia that is characterized by the loss of motor
coordination in the limbs and head.  This form of ataxia usually begins in
infancy.  An early sign of this disorder is impaired muscle coordination
which is most evident when walking.  At 3 to 6 years of age dilated blood
vessels (telangiectasias) appear in the eyes.  These widened blood vessels
also appear eventually on the face and the roof of the mouth.  There is an
increase in the risk of sinus and respiratory infections.  Patients with
Ataxia Telangiectasia are also more susceptible to tumors (neoplasms) and
premature aging.  In some cases this disease has been associated with an
immune deficiency (IgA or IgE).  Mental development may be normal in the
early stages of this disorder but loss of intellectual capacities may occur
during the 2nd decade of life.   Ataxia Telangiectasia may be misdiagnosed as
Friedreich's Ataxia until Telangiectasias appear.  (For more information on
this disorder, choose "Ataxia Telangiectasia" as your search term in the Rare
Disease Database).

Olivopontocerebellar Atrophy (OPCA) is a group of five inherited forms of
ataxias (impaired ability to coordinate movement).  It is characterized by
the progressive neurological degeneration (gradual deterioration) affecting
certain areas of the brain.  The loss of these brain cells (neurons) may
result in impaired muscle coordination, tremor, involuntary movements and
speech disturbance (dysarthria).  A wide variety in severity and age of onset
may be found in all types of Olivopontocerebellar Atrophy.  (For more
information on this disorder, choose "Olivopontocerebellar Atrophy" as your
search term in the Rare Disease Database).

Therapies:  Standard

Treatment of Friedreich's Ataxia is symptomatic and supportive.  Continuous
medical supervision to avoid potential complications involving the heart,
lungs, spine, bones and muscles are recommended.  Prevention of pneumonia is
a challenge in the care of people in the advanced stages of Friedreich's
Ataxia.

Heart problems and/or diabetes associated with Friedreich's Ataxia may be
treated with medication.  The patient may also be more susceptible to
infection.  Insulin is usually effective in controlling Diabetes Mellitus.
Vision and hearing problems may be alleviated with either corrective devices,
drugs, or in some cases surgery.  Mental functions usually remain unaffected
but emotional strain can affect patients and their families.  In such cases,
psychological counseling may be helpful.  Genetic counseling can assist many
patients and families when they are affected by one of the hereditary
ataxias.  Prenatal diagnosis is available for pregnant women with
Friedreich's Ataxia.

Physical therapy may be helpful when recommended by a physician.  Various
aids may assist muscular movement.  Orthopedic surgery or braces may help
curvature of the spine and abnormalities of the feet, but should be carefully
considered after consultation with a neurologist and orthopedist.

Drugs may be useful in treating some symptoms of Friedreich's Ataxia.
Propanalol may be effective against static tremors, and less often against
intention tremors.  Static tremors can occur when the affected individual is
not moving, whereas intention tremors occur when the patient makes
intentional movements.  Dantrolene Sodium may help some patients with muscle
spasms of the legs.  These drugs should be carefully monitored by a physician
to limit the possibility of toxicity.  Other treatment is symptomatic and
supportive.

Therapies:  Investigational

Treatment for Friedreich's Ataxia with a multiprogrammable spinal cord
stimulator involves epidural spinal electrostimulation (ESES).  This is a
medical device under investigation for treatment of motor dysfunction.  The
device can be surgically implanted over the spine and may be of therapeutic
benefit to patients with some types of Ataxia as well as other neuromuscular
disorders.  The procedure may be tried when conservative measures prove
ineffective.  The goal is to increase the range of mobility and alleviate
muscle spasms and pain.  For further information on experimental ESES
devices, physicians may contact:

     Neuromed
     5000 Oakes Rd.
     Ft.  Lauderdale, FL  33314
     [phone]

This disease entry is based upon medical information available through
August 1992.  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 Friedreich's Ataxia, please contact:

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

     National Ataxia Foundation
     500 Twelve Oaks Center
     15500 Wayzata Blvd.
     Wayzata, MN  55391
     [phone]

     NIH/National Institute of Neurological Disorders & Stroke (NINDS)
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]
     [phone]

For information on genetics, and genetic counseling referrals, please
contact:

     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]

For More Information on Scoliosis, contact:

     National Scoliosis Foundation, Inc.
     72 Mount Auburn St.
     Watertown, MA  02172
     [phone]

For More Information on Diabetes, contact:

     American Diabetes Association
     National Service Center
     1660 Duke Street
     Alexandria, VA  22314

     International Tremor Foundation
     360 W. Superior St.
     Chicago, IL  60610
     [phone]

The following organization provides clinical services for people with
Friedreich's Ataxia including the provision of orthopedic aids, recreation at
summer and winter camps, and transportation assistance.

     Muscular Dystrophy Association, National Office
     3561 E. Sunrise Dr.
     Tucson, AZ  85718
     [phone]

References

BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief;
Blackwell Scientific Publications, 1990.  Pp. 203-204.

MENDELIAN INHERITANCE IN MAN, 9th Ed.:  Victor A. McKusick, Editor:  Johns
Hopkins University Press, 1990.  Pp. 1184-1186.

CECIL TEXTBOOK OF MEDICINE, 19th Ed.:  James B. Wyngaarden, and Lloyd H.
Smith, Jr., Editors; W.B. Saunders Co., 1990.  Pp. 2138.

THE FRIEDREICH ATAXIA GENE ASSIGNED TO CHROMOSOME 9q13-Q21 BY MAPPING
TIGHTLY LINKED MARKERS AND SHOWS LINKAGE DISEQUILIBRIUM WITH D9S15.  A.
Hanauer, M. Chery, R. Fujita, A.J. Driesel, S. Gilgenkfrantz and J.L. Mandel;
American Journal of Human Genetics (Jan. 1990; 46(1)):  Pp. 133-137.