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Dystonia

Dystonia

Definition

Dystonia is a disabling movement disorder characterized by sustained contraction of muscles leading to twisting distorted postures. Dystonia may affect various parts of the body and has multiple causes, making classification and diagnosis challenging. The etiology behind the various forms of dystonia is unknown, although abnormal functioning of the cerebral cortex and basal ganglia and other pathways involved in movement are presumed. Clinical and basic science research on humans and primates, and identification of multiple genes causing dystonia have improved the understanding and treatment of this debilitating disorder.

Description

Dystonia as a term was first coined by Oppenheim in 1911 in reference to a childhood-onset syndrome he termed dystonia musculorum deformans. This entity, known as idiopathic torsion dystonia today, was noted to run in families, and although presumably inherited, was only recently proven to be of genetic cause. There is a wide range of variability in the manifestation of clinical symptoms of dystonia. Due to its various causes, dystonia is seen as a syndrome rather than a disease.

Dystonia can be classified by age of onset, cause, or by distribution of the body parts affected. Dystonia localized to a single body part such as the hand or neck is referred to as focal. Among body parts affected in focal dystonia, the eyelids, mouth, muscles controlling the voice, neck, hand, or arm may be affected. Dystonia localized to two contiguous body parts is referred to as segmental. Dystonia affecting body parts that are not next to each other is referred to as multifocal. Dystonia affecting one segment and another body part is classified as generalized. It may also affect only one half of the body and be called hemidystonia. Dystonia with a known environmental cause is referred to as secondary. The cause of primary or idiopathic dystonias is unknown or genetic.

The course and severity of dystonic symptoms may change over the duration of the illness. Symptoms may initially involve one body part and then spread to other body parts. The likelihood of spread often depends on the age and site of onset of symptoms. Early onset dystonia may start in a limb but tends to become generalized. Adult onset dystonia may start in the neck or face muscles and tends not to spread. Dystonia may first occur only with voluntary movements, but in time, occur at rest as well.

Demographics

Dystonia follows Parkinson's disease and essential tremor as the most frequent movement disorder. Prevalence is estimated as 3.4 per 100,000 for generalized forms and 29.5 per 100,000 for focal dystonia. Early onset dystonia may be more frequent in patients of Jewish ancestry, especially from Eastern Europe or Ashkenazi background.

Causes and symptoms

Causes

The exact cause of dystonia is unknown. Ongoing research on dystonia is directed at examining the abnormal brain activity in different parts of the brain such as the basal ganglia and cerebral cortex. The basal ganglia are a collection of nerve cells that are part of the brain pathways important for regulating aspects of normal movement. Abnormalities in the processing of information in these pathways are thought to underlie the various movement disorders such as Parkinson's disease, Huntington's disease, tremor, and dystonia. There is evidence for abnormalities in the spinal cord and peripheral nerves as well, suggesting that dystonia may involve abnormalities at multiple levels of the nervous system. Patients with dystonia may have abnormal touch perception and sensation, and theories propose that there may be defects in the preparation of movement as well as the translation of sensation to movement. Dystonia can be classified by cause into primary and secondary forms. Primary or idiopathic dystonia is presumed to be of genetic or unknown cause, whereas secondary dystonias are due to an attributable cause.

Primary dystonia

Primary or idiopathic dystonias have no identifiable etiology and are presumed to be genetic in cause. There are currently at least 13 different genetic dystonia syndromes, although only a few genes have actually been isolated. The only identified gene for primary dystonia is DYT1 on chromosome 9. DYT1 dystonia tends to occur in childhood and starts in a limb only to generalize. The appearance of the dystonia may differ in individuals with the same genetic abnormality, suggesting that there are environmental factors involved as well. Primary genetic dystonias may appear in multiple family members, but most are due to new mutations in genes and referred to as sporadic. Primary dystonias tend to develop gradually over the course of months to years.

Secondary dystonia

Secondary dystonia can be caused by a structural abnormality of the brain such as a stroke or infection, drugs or various toxins or metabolic abnormalities. These tend to occur over the course of days to weeks due to the nature of an inciting insult. Dystonia may occur after birth trauma and may be delayed in onset for up to a decade or later. Some may occur as part of a larger disease process affecting other parts of the body such as Wilson's disease, a defect of metabolism of copper that causes abnormal liver function and movement problems such as dystonia or tremor. Usually an abnormality will be found on brain imaging studies such as MRI or CT scan . Patients taking medications for psychiatric diseases such as schizophrenia or psychosis may develop dystonia as a drug reaction. Dystonia may be feigned as part of a psychiatric disorder and is then known as psychogenic.

Other dystonias

Dystonia may also be associated with other neurologic disorders. These are classified as dystonia-plus syndromes. Dystonia may be associated with Parkinson's disease or myoclonus , another movement disorder which consists of muscle jerking. Dystonia may be part of a larger syndrome of neurodegenerative disorders, a group of diseases which are caused by degeneration of nerve cells in certain portions of the brain. Such disorders include Huntington's disease and Parkinson's disease.

Symptoms

The symptoms of dystonia depend on the body part affected. Dystonia localized to the face may involve repetitive blinking, tongue protrusion, or jaw clenching. Blinking can become so severe that the patient can not see due to inability to open the eyes. Dystonia affecting the neck may lead to sustained flexion, extension, or twisting postures of the neck known as torticollis. Some dystonias are task-specific and only arise during the performance of certain tasks such as writing, typing, or playing instruments. The progression of these symptoms can lead to severe disability and inability to perform daily work. Generalized dystonia, the most severe form, can present as twisting movements of the head, trunk, and arms, completely disabling the affected individual. Dystonia can often be associated with a tremor in the affected body part. All forms of dystonia impair normal movement and daily function to some degree. Dystonia can be worsened by stress and anxiety, whereas it may be relieved with relaxation and sleep. Symptoms may be improved by touching various parts of the body in a phenomenon called a "sensory trick."

Diagnosis

The diagnosis of dystonia is clinical and is usually made by a neurologist who may have expertise with movement disorders. Investigation of dystonia will usually involve a physical examination and medical history taken by the neurologist to look for secondary causes such as drug exposure or stroke or other family members affected, suggesting a genetic cause. An MRI of the brain may be performed to look for a structural abnormality causing the symptoms. Laboratory testing may reveal abnormalities of copper metabolism associated with Wilson's disease. Genetic testing for the DYT1 gene is not performed unless the dystonia is early in onset or there is a family history of similar symptoms.

Treatment team

Treatment for dystonia involves the interaction between a neurologist, psychiatrists, and physical and occupational therapists. Treatment may involve a neurosurgeon for symptoms that do not respond to medical management. Dystonia of childhood onset is treated by a pediatric neurologist cooperating with pediatricians and pediatric therapists.

Treatment

Treatment for dystonia is usually directed towards management of the symptoms and depends on the type of dystonia. Dystonia that is associated or caused by known etiologies such as drugs, Wilson's disease, or dopa-responsive dystonia may be improved by treating the underlying disease with resolution of symptoms. The various treatments available may be grouped into oral medications, botulinum toxin injections, and surgical modalities.

Medications

Various oral medications are available for the symptomatic treatment of dystonia. Among these are various medications that affect different neurochemical systems thought to be important in causing dystonia. Some patients with symptoms of early onset may have dystonia that responds dramatically to levodopa. Anticholinergics , dopamine depleting agents, benzodiazepines , baclofen, or atypical antipsychotics may be tried as well.

Botox

Chemical denervation using botulinum toxin has been used for many movement disorders including dystonia. Botulinum toxin blocks the transmission of nerve impulses to the muscle and paralyzes the overactive muscles involved. Focal forms of dystonia are more amenable to treatment due to the ease of localizing injectable muscles and less extensive involvement. Botox may be used in generalized dystonia to facilitate improvement in select muscles needed for daily function such as the arms and legs.

Surgical treatment

Selective destruction or high frequency stimulation of nerve centers involved in causing dystonia has been useful in treating selected patients with disabling symptoms. Patients with generalized dystonia or hemidystonia may benefit due to the widespread nature of symptoms, limiting the efficacy of medications and botox injections. Surgical lesioning of nerve cells in the globus pallidus or stimulation of cells in the globus pallidus or subthalamic nucleus have been shown to be effective in treating the symptoms of dystonia. The long-term benefit of surgical therapies on symptoms of dystonia has yet to be validated.

Recovery and rehabilitation

Symptoms of dystonia may fluctuate over the course of years. The course of disease in any given individual can not be predicted. Some may improve spontaneously, whereas others may progress and spread to involve other body parts. Physical therapists may aid in the treatment of symptoms of dystonia. Treatment is focused on maintaining or improving the patient's ability to walk. Occupational therapy may be helpful in improving hand use.

Clinical trials

Several clinical trials are currently in effect for treatment of dystonia. The National Institutes of Health (NIH) and National Institutes of Neurological Diseases and Stroke (NINDS) are recruiting patients for trials examining the effect of different medications, botulinum toxin treatment, and surgical treatment for patients with dystonia. Studies are also ongoing to study the effect of electrical stimulation of the brain and nerves with magnetic fields to treat dystonia. Updated information on clinical trials can be found at the National Institutes of Health clinical trials website at www.clinicaltrials.org.

Prognosis

The prognosis for dystonia depends on the distribution and the cause. The initial site of symptoms may predict the prognosis. Patients with symptoms that start in the leg have a higher likelihood (90%) of progression to involve other body parts and become generalized. Patients with symptoms starting in the neck and later in onset have a much lower likelihood of spread. Most focal dystonias respond to medications or botulinum toxin. Refractory and generalized dystonia may require surgical management. Most patients have a normal life expectancy although with continued disabling symptoms.

Special concerns

Educational and social needs

Dystonia in many cases is a chronic illness and due to the physical limitations and often disfiguring symptoms, may lead to feelings of depression or anxiety. These feelings may require treatment by a psychiatrist if severe enough. It is important for patients with dystonia to continue to be involved in community activities and social events.

Resources

BOOKS

Bradley, Walter G., Robert Daroff, Gerald Fenichel, and C. David Marsden. Neurology in Clinical Practice. Newton, MA: Butterworth-Heinemann, 2000.

Rowland, Lewis, ed. Merritt's Textbook of Neurology. Philadelphia, PA: Lippincott Williams & Wilkins, 2000.

PERIODICALS

Klein, C., and L. J. Ozelius. "Dystonia: clinical features, genetics, and treatment." Current Opinion in Neurology 15 (2002): 491497.

Langlois, M., F. Richer, and S. Chouinard. "New Perspectives on Dystonia." Canadian Journal of Neurological Sciences 30, Suppl. 1 (2003): S34S44.

Volkmann, J., and R. Benecke. "Deep Brain Stimulation for Dystonia: Patient Selection and Evaluation." Movement Disorders 17 (2002): S112S115.

WEBSITES

NINDS Dystonias Information Page. National Institutes of Neurological Disorders and Stroke (NINDS). July 1, 2001. (June 7, 2004). <http://www.ninds.nih.gov/health_and_medical/disorders/the_dystonias.htm>

ORGANIZATIONS

Dystonia Medical Research Foundation. 1 East Wacker Drive, Suite 2430, Chicago, IL 60601-1905. (312) 755-0198; Fax: (312) 803-0138. [email protected]/ <http://www.dystonia-foundation.org>.

Worldwide Education & Awareness for Movement Disorders (WE MOVE). 204 West 84th Street, New York, NY 10024. (212) 875-8312 or (800) 437-6682; Fax: (212) 875-8389. [email protected] <http://www.wemove.org>.

Peter T. Lin, MD

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dystonia

dystonia (dis-toh-niă) n. muscle dysfunction characterized by spasms or abnormal muscle contraction. Forms of dystonia include torticollis, blepharospasm, and writer's cramp. Another form is a postural disorder often associated with disease of the basal ganglia in the brain.
dystonic adj.

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Dystonia

Dystonia

Definition

Dystonia is a group of complex neurological movement disorders. While the disorders vary in their symptoms, causes, progression, and treatment, dystonia is characterized by involuntary muscle contractions and spasms that result in abnormal postures and movements. Focal dystonias—which affect a single part of the body, such as the face, arms, or vocal chords—are the most common.

Description

Dystonia is not a single disease, but a group of disorders with a variety of symptoms. The most common characteristic of dystonia is twisting, repetitive, and sometimes painful movements that affect a specific part of the body, such as the arms, legs, trunk, neck, eyelids, face, or vocal cords. Cervical dystonia, which affects the head and neck, is the most common adult form of dystonia, followed by blepharospasm (eyelids), spasmodic dysphonia (larynx), and limb dystonias (hands).

Researchers believe that dystonia is caused by a malfunction in the basal ganglia, the part of the brain involved in regulating voluntary and involuntary movement. A Berlin neurologist, Hermann Oppenheim, first coined the term "dystonia" in 1911 after observing muscle spasm and variation in muscle tone in several of his young patients. The term was widely accepted and used by neurologists; however, the definition has changed over time.

Today dystonia is classified in several ways, based on cause, location, and age at onset.

Dystonia can be caused by many different factors. It may occur due to trauma, stroke, certain infections and diseases (e.g. Wilson disease , multiple sclerosis), reactions to certain neuroleptic or antipsychotic drugs (e.g. haloperidol or chlorpromazine), birth injury, or heavy-metal or carbon monoxide poisoning. This type of dystonia is called secondary or symptomatic dystonia. About half of dystonia cases have no connection to disease or injury and are referred to as primary dystonia. Many of these cases appear to be inherited.

The most useful classification for physicians is location, or distribution of the dystonia. Focal dystonia involves a single body part while multifocal dystonia affects multiple body parts. In generalized dystonia, symptoms begin in an arm or a leg and advance, eventually affecting the rest of the body.

The patient's age at the onset of symptoms helps physicians identify the cause and determine the probability of disease progression. Dystonia that begins in childhood is often hereditary, begins in the leg or (less commonly) the arm, and may progress to other parts of the body. Dystonia that begins in adolescence (early onset dystonia) may be hereditary, often begins in the arm or neck, and is more likely to progress than the childhood form. Adult-onset dystonia typically begins as focal or multifocal and is sporadic in origin.

Genetic profile

The majority of primary dystonia cases are believed to be hereditary and occur as the result of a faulty gene . Most cases of early-onset primary dystonia are due to a mutation in the DYT-1 gene, which was first identified as a factor in the disorder in 1987.

Dystonia appears when an individual has one copy of the mutated gene and one copy of the normal gene; however, only 30–40% of individuals with the mutated genes develop symptoms.

Demographics

Dystonia affects more than 300,000 people in North America, affecting all races and ethnic groups. Early onset idiopathic torsion dystonia has a higher frequency among Ashkenazi Jews—Jews of Eastern European ancestry.

Dystonia is the third most common movement disorder, after Parkinson disease and tremor.

Signs and symptoms

Early symptoms of dystonia may include a deterioration in handwriting, foot cramps, tremor, voice or speech difficulties, and a tendency of one foot to pull up or drag while walking. Initially, the symptoms may be very mild and only noticeable after prolonged exertion, stress, or fatigue. Over a period of time, the symptoms may become more noticeable and widespread.

Symptoms may first occur in childhood (between the ages of 5 and 17 years) or early adulthood. In general, the earlier the onset of symptoms, the greater the chance that the disease will progress with advancing age.

Diagnosis

There is no specific diagnostic test for dystonia and the diagnosis is often based on clinical signs and symptoms. Diagnosis may be difficult because the signs are similar to those of other disorders; the involuntary muscle contractions are often incorrectly attributed to stress, stiff neck, dry eyes, tics, or psychogenic or neurological disorders. According to Mount Sinai Medical Center, 90% of dystonia patients are initially misdiagnosed.

One thing that is helpful in differentiating dystonic movements from those caused by other disorders is the timing of the movements. Dystonic movements tend to increase during activity, nervousness, and emotional stress; and usually disappear during sleep.

Treatment and management

There is no cure for dystonia. However, symptoms such as spasms and pain can usually be managed with a combination of treatments.

No one treatment has proven universally effective. A physician's approach to treatment is typically three-tiered, encompassing oral medications, injections of therapeutic agents (e.g. botulinum toxin) directly into dystonic muscle, and surgery. Surgery, which involves cutting nerves and muscles or placing a lesion in the basal ganglia to reduce movement, is usually reserved for the most severe cases. Alternative medicine, such as physical therapy, speech therapy, and biofeedback, may also have a role in treatment management.

The cause and location of a patient's dystonia will play a factor in the treatment methods chosen by the physician. In secondary dystonia, treating the underlying cause may prove effective in improving or eliminating the associated symptoms. Patients with focal dystonia often respond best to targeted methods—such as injections of botulinum toxin or surgery—while patients with dystonia may first need to be treated with oral medications to alleviate the multiple symptoms.

Prognosis

Dystonia is not fatal; however, it is a chronic disorder and prognosis can be difficult to predict.

Resources

PERIODICALS

Adler, Charles H. "Strategies for Controlling Dystonia; Overview of Therapies That May Alleviate Symptoms." Postgraduate Medicine (October 2000). <http://www.postgradmed.com/issues/2000/10_00/adler.htm>.

Ozelius, Laurie J, Jeffrey W. Hewett, Curtis E. Page, Susan B. Bressman, Patricia L. Kramer, Christo Shalish, Deborah de Leon, Mitchell F. Brin, Deborah Raymond, David P. Corey, Stanley Fahn, Neil J. Risch, Alan J. Buckler, James F. Gusella, and Xandra O. Breakefield. "The Early-Onset Torsion Dystonia Gene (DYT1) Encodes an ATP-Binding Protein." Nature Genetics 17 (September 1997): 40.

ORGANIZATIONS

Bachmann-Strauss Dystonia & Parkinson Foundation, Inc. Mount Sinai Medical Center, One Gustave L. Levy Place, Box 1490, New York, NY 10029. (212) 241-5614. <http://www.dystonia-parkinsons.org>.

Dystonia Medical Research Foundation. One East Wacker Dr., Suite 2430, Chicago, IL 60601. (312) 755-0198. <http://www.dystonia-foundation.org>.

National Institute of Neurological Disorders and Stroke. 31 Center Drive, MSC 2540, Bldg. 31, Room 8806, Bethesda, MD 20814. (301) 496-5751 or (800) 352-9424. <http://www.ninds.nih.gov>.

National Organization for Rare Disorders (NORD). PO Box 8923, New Fairfield, CT 06812-8923. (203) 746-6518 or (800) 999-6673. Fax: (203) 746-6481. <http://www.rarediseases.org>.

WE MOVE (Worldwide Education and Awareness for Movement Disorders). Mount Sinai Medical Center, One Gustave L. Levy Place, Box 1490, New York, NY 10029. (800) 437-6682. <http://www.wemove.org>.

WEBSITES

"Gene Sequenced for Disabling Childhood Movement Disorder: Early-Onset Torsion Dystonia Protein Found." National Institute of Neurological Disorders and Stroke. September 3, 1997. <www.ninds.nih.gov/news_and_events/pressrelease_disabling_childhhod_movement_090397.htm>.

"Early Onset Primary Dystonia." GeneClinics. March 30, 1999. <www.geneclinics.org/profiles/dystonia>.

Michelle L. Brandt

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Dystonia

Dystonia

Definition

Dystonia is a group of complex neurological movement disorders. While the disorders vary in their symptoms, causes, progression, and treatment, dystonia is characterized by involuntary muscle contractions and spasms that result in abnormal postures and movements. Focal dystonias—which affect a single part of the body, such as the face, arms, or vocal chords—are the most common.

Description

Dystonia is not a single disease, but a group of disorders with a variety of symptoms. The most common characteristic of dystonia is twisting, repetitive, and sometimes painful movements that affect a specific part of the body, such as the arms, legs, trunk, neck, eyelids, face, or vocal cords. Cervical dystonia, which affects the head and neck, is the most common adult form of dystonia, followed by blepharospasm (eyelids), spasmodic dysphonia (larynx), and limb dystonias (hands).

Researchers believe that dystonia is caused by a malfunction in the basal ganglia, the part of the brain involved in regulating voluntary and involuntary movement. A Berlin neurologist, Hermann Oppenheim, first coined the term "dystonia" in 1911 after observing muscle spasm and variation in muscle tone in several of his young patients. The term was widely accepted and used by neurologists; however, the definition has changed over time.

Today dystonia is classified in several ways, based on cause, location, and age at onset.

Dystonia can be caused by many different factors. It may occur due to trauma, stroke, certain infections and diseases (e.g., Wilson disease , multiple sclerosis ), reactions to certain neuroleptic or antipsychotic drugs (e.g., haloperidol or chlorpromazine), birth injury, or heavy-metal or carbon monoxide poisoning. This type of dystonia is called secondary or symptomatic dystonia. About half of dystonia cases have no connection to disease or injury and are referred to as primary dystonia. Many of these cases appear to be inherited.

The most useful classification for physicians is location, or distribution of the dystonia. Focal dystonia involves a single body part while multifocal dystonia affects multiple body parts. In generalized dystonia, symptoms begin in an arm or a leg and advance, eventually affecting the rest of the body.

The patient's age at the onset of symptoms helps physicians identify the cause and determine the probability of disease progression. Dystonia that begins in childhood is often hereditary, begins in the leg or (less commonly) the arm, and may progress to other parts of the body. Dystonia that begins in adolescence (early on-set dystonia) may be hereditary, often begins in the arm or neck, and is more likely to progress than the childhood form. Adult-onset dystonia typically begins as focal or multifocal and is sporadic in origin.

Genetic profile

The majority of primary dystonia cases are believed to be hereditary and occur as the result of a faulty gene . Most cases of early-onset primary dystonia are due to a mutation in the DYT-1 gene, which was first identified as a factor in the disorder in 1987.

Dystonia appears when an individual has one copy of the mutated gene and one copy of the normal gene; however, only 30–40% of individuals with the mutated genes develop symptoms.

Demographics

Dystonia affects more than 300,000 people in North America, affecting all races and ethnic groups. Early onset idiopathic torsion dystonia has a higher frequency among Ashkenazi Jews—Jews of Eastern European ancestry.

Dystonia is the third most common movement disorder, after Parkinson disease and tremor.

Signs and symptoms

Early symptoms of dystonia may include a deterioration in handwriting, foot cramps, tremor, voice or speech difficulties, and a tendency of one foot to pull up or drag while walking. Initially, the symptoms may be very mild and only noticeable after prolonged exertion, stress, or fatigue. Over a period of time, the symptoms may become more noticeable and widespread.

Symptoms may first occur in childhood (between the ages of 5 and 17 years) or early adulthood. In general, the earlier the onset of symptoms, the greater the chance that the disease will progress with advancing age.

Diagnosis

There is no specific diagnostic test for dystonia and the diagnosis is often based on clinical signs and symptoms. Diagnosis may be difficult because the signs are similar to those of other disorders; the involuntary muscle contractions are often incorrectly attributed to stress, stiff neck, dry eyes, tics, or psychogenic or neurological disorders. According to Mount Sinai Medical Center, 90% of dystonia patients are initially misdiagnosed.

One thing that is helpful in differentiating dystonic movements from those caused by other disorders is the timing of the movements. Dystonic movements tend to increase during activity, nervousness, and emotional stress; and usually disappear during sleep.

Treatment and management

There is no cure for dystonia. However, symptoms such as spasms and pain can usually be managed with a combination of treatments.

No one treatment has proven universally effective. A physician's approach to treatment is typically three-tiered, encompassing oral medications, injections of therapeutic agents (e.g., botulinum toxin) directly into dystonic muscle, and surgery. Surgery, which involves cutting nerves and muscles or placing a lesion in the basal ganglia to reduce movement, is usually reserved for the most severe cases. Alternative medicine, such as physical therapy, speech therapy, and biofeedback, may also have a role in treatment management.

The cause and location of a patient's dystonia will play a factor in the treatment methods chosen by the physician. In secondary dystonia, treating the underlying cause may prove effective in improving or eliminating the associated symptoms. Patients with focal dystonia often respond best to targeted methods—such as injections of botulinum toxin or surgery—while patients with dystonia may first need to be treated with oral medications to alleviate the multiple symptoms.

Prognosis

Dystonia is not fatal; however, it is a chronic disorder and prognosis can be difficult to predict.

Resources

PERIODICALS

Adler, Charles H. "Strategies for Controlling Dystonia; Overview of Therapies That May Alleviate Symptoms."

Postgraduate Medicine (October 2000). <http://www.postgradmed.com/issues/2000/10_00/adler.htm>.

Ozelius, Laurie J., et al. "The Early-Onset Torsion Dystonia Gene (DYT1) Encodes an ATP-Binding Protein." Nature Genetics 17 (September 1997): 40.

ORGANIZATIONS

Bachmann-Strauss Dystonia & Parkinson Foundation, Inc. Mount Sinai Medical Center, One Gustave L. Levy Place, Box 1490, New York, NY 10029. (212) 241-5614. <http://www.dystonia-parkinsons.org>.

Dystonia Medical Research Foundation. One East Wacker Dr., Suite 2430, Chicago, IL 60601. (312) 755-0198. <http://www.dystonia-foundation.org>.

National Institute of Neurological Disorders and Stroke. 31 Center Drive, MSC 2540, Bldg. 31, Room 8806, Bethesda, MD 20814. (301) 496-5751 or (800) 352-9424. <http://www.ninds.nih.gov>.

National Organization for Rare Disorders (NORD). PO Box 8923, New Fairfield, CT 06812-8923. (203) 746-6518 or (800) 999-6673. Fax: (203) 746-6481. <http://www.rarediseases.org>.

WE MOVE (Worldwide Education and Awareness for Movement Disorders). Mount Sinai Medical Center, One Gustave L. Levy Place, Box 1490, New York, NY 10029. (800) 437-6682. <http://www.wemove.org>.

WEBSITES

"Early Onset Primary Dystonia." GeneClinics. March 30, 1999. <www.geneclinics.org/profiles/dystonia>.

"Gene Sequenced for Disabling Childhood Movement Disorder: Early-Onset Torsion Dystonia Protein Found." National Institute of Neurological Disorders and Stroke. September 3, 1997. <www.ninds.nih.gov/news_and_events/pressrelease_disabling_childhhod_movement_090397.htm>.

Michelle L. Brandt

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