Kennedy's Disease (also known as Spinal Bulbar Muscular Atrophy, SBMA, or Kennedy's Syndrome) is a rare and currently incurable and non-treatable X-linked recessive genetic progressive neuro-muscular disease. Both the spinal and bulbar neurons are affected causing muscle weakness and wasting (atrophy) throughout the body which is most noticeable in the extremities (legs/arms), it is especially noticeable in the face and throat, and causes speech and swallowing difficulties, major muscle cramps as well as other symptoms (please see "KD Symptoms" section of this Web site for more detail).

KD is an adult-onset disease with symptoms usually appearing between the ages of 30 and 50. However, earlier onsets have been recorded.

Generally males with this inherited gene develop symptoms, while females with this gene are usually just carriers. Although, in rare cases, females have been known to exhibit symptoms as well. Life expectancy is noted to be at or almost normal.

It is estimated that 1 in 40,000 individuals worldwide have Kennedy's Disease. However, many go misdiagnosed or not diagnosed for years. The number one misdiagnosis is Lou Gehrig's Disease (ALS) a fatal disease.

What causes the symptoms that are associated with KD:

Motor neurons are long nerve cells that extend from your spinal cord to your muscles.  These nerve cells fire to make your muscles contract. In KD (Kennedy's Disease) the nerve cells become dysfunctional and eventually die, leaving the muscle unable to contract

The androgen receptor is a protein that lives inside the nerve cell.  Lots of cells have the androgen receptor protein, but motor neurons have more than most. The androgen receptor sits around waiting for testosterone to come and bind to it. The binding of testosterone to androgen receptor somehow kicks off the disease. Since men have much higher levels of testosterone, they are affected by the disease.

Wikipedia - Definition of Kennedy's Disease (also genetic chart)

Description of Spinal Bulbar Muscular Atrophy (aka Kennedy's Disease)

Kennedy's Disease can be easily diagnosed with a simple DNA blood test.  DNA test labs are listed here.

If you are a Physician or Neurologist Click Here to see the specifics of the DNA blood test