Kennedy's Disease Association

A Public Benefit, Non-Profit Organization

Our Focus Remains on Research, Education and Support

The Kennedy’s Disease Association has worked to educate others about this lesser-known disease and to support clinical research efforts. We distributed information to more than 10,000 neurologists to help them recognize clinical signs and symptoms of Kennedy’s Disease.


Will my child be born with this DNA defect?

It takes an enormous amount of money to fund research…more than any of us can afford alone, but together, we are capable of great accomplishments. We are searching for available foundation grants, but the process is lengthy. We need researchers to continue their work, and it is only the KDA that makes funding this disease a priority.


Kennedy’s Disease Knows No Boundaries...

It is passed on from generation to generation in families worldwide. Males generally inherit the disease symptoms and females are the carriers. The defect is in the ‘X’ Chromosome that makes testosterone almost a poison to his body.


What is Kennedy's Disease?

Kennedy’s Disease (spinal and bulbar muscular atrophy) is an adult-onset “X” linked inherited disease with symptoms usually beginning to appear between the ages of 30 and 50. However, onset has also been reported as early as in the teens and as late as the 60s.


Kennedy's Disease Symptoms PDF Print E-mail
Medical Term:
Bulbar Signs The Bulbar muscles are those supplied by the motor nerves coming off the brain stem which control breathing, swallowing, talking and other functions of the throat. Bulbar signs are problems with these functions.


Trouble swallowing. (One of the Bulbar signs.)
Intention Tremor Hand tremors when trying to do something.
Normal Babinski Normal plantar response, ie., when the bottom of the foot is scraped, the toes bend down. An abnormal response would be an upward bending of the toes indicating a problem in the brain itself.

Lower Motor Neuropathy

The lower motor nerves are those that run from the spinal cord to the muscles that they stimulate to move. Loss of that nerve leads to weakness and wasting of the muscle.
Primary Sensory Neuropathy Numbness over certain areas. Loss of sensation.

Decreased or Absent Deep Tendon Reflexes


When a doctor taps the knee with his hammer there is no response.

Fasciculations Twitching of small muscles without purposeful movement, that can be seen through the skin.
Cramps Large muscle spasms.
Postural Tremor Shaky muscles with certain positions.
Muscular Atrophy Wasting and shrinkage of muscles that occurs when the lower motor nerve does not stimulate the muscle adequately.

Hypertrophied Calves


Calf muscles that become thicker because of cramps.



Enlarged breasts.
Androgen Deficiency Loss of masculinizing effect.

Estrogen Excess


More of an apparent estrogen effect because of the lost of masulinizing effect.
Impotence Erectile dysfunction.
Reduced Fertility Low sperm count.

Testicular Atrophy


Testicles become smaller and less functional.
Miscellaneous Characteristics:
Late Apparent Onset Symptoms apparent in late 30's and after.
Slow Progression Near-normal lifespan.

Asymmetry of Clinical Signs


Muscles of one side may be more affected than the same muscles on the other side.
Elevated Serum Creatine Kinase Elevation of CPK enzyme in the blood test.  Can be confused with the enzyme released during a heart attack.
Genetic Test

The Kennedy's Disease gene can be found in the blood by a genetic laboratory test in both affected males and carrier females.