Handbook of Genetic Counseling/Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS)

What is ALS?

• a degenerative disease of the nervous system, affecting the brain cells (motor neurons) that carry impulses from the brain and spinal cord to the muscles
• results in muscular weakness and the progressive wasting of muscles that have lost their nerve supply
• the most common form of motor neuron disease
• patients have difficulty speaking, swallowing, and breathing
• death usually follows within 3 to 5 years
• onset commonly occurs between the ages of 35 and 65
• slightly more common in men than in women
• 5-10% of ALS cases are familial
• The gene is inherited as an autosomal dominant genetic trait and is located on the long arm of chromosome 21
• 90% of ALS cases are sporadic, with no obvious genetic cause
• manifests differently amongst patients, likely due to environmental agents interacting with genetic susceptibility
• ALS strikes 2 to 7 out of every 100,000 people in the USA
• no specific treatment yet exists, and patients can be aided only by supportive therapy
• ALS is also called Lou Gehrig's disease after the baseball star who died of it

Symptoms

• early symptoms include slight muscle weakness, clumsy hand movements, and/or difficulty performing tasks that require delicate movements of the fingers and/or hands
• muscular weakness in the legs may cause tripping and falling
• difficulty swallowing (dysphagia)
• speech may be slowed
• progressive weakness of the lips and impairment and/or loss of function of the tongue, mouth, and/or voice box (bulbar symptoms)
• leg cramps may occur during the night, most frequently in the calf and/or thigh muscles
• uncontrolled twitching of muscles (fasciculations)
• exaggerated deep muscle reflexes.
• severe weight loss occurs in approximately 5% of cases
• increased risk for respiratory failure and abnormally low levels of oxygen in the blood
• increased risk for acute inflammation of the lungs, caused by the inhalation of food or stomach contents (aspiration pneumonia).
• an overall decrease in the ability to move may also result in inadequate nutrition

Resources and Support Groups

• The ALS Association

the only national not-for-profit health agency dedicated to the fight against ALS

the mission of The ALS Association (ALSA) is to find a cure for and improve living with amyotrophic lateral sclerosis

toll-free information and referral service available to patients, caregivers and family members, staffed by ALSA Patient Service Co-ordinators.

1-800-782-4747 (Monday through Friday 7:30am to 4:00pm PST)

to reach ALSA's Patient Services department by e-mail, contact alsinfo@alsa-national.org.

Suite 150

27001 Agoura Road

Calabasas Hills, CA 91301

(818) 880-9007

• NIH/National Institute of Neurological Disorders & Stroke (NINDS)

9000 Rockville Pike

Bethesda MD 20892

(301) 496-5751

(800) 352-9424

• ALS Canada:
• ALS Society of British Columbia:

Notes

The information in this outline was last updated in 2002.