Kennedy's Disease Association

A Public Benefit, Non-Profit Organization

"Every few days a baby boy is born with this DNA defect"

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.

2000 - June 10, Kennedy’s Symposium (Spinal Bulbar Muscular Atrophy –SBMA)

FSMA Conference of the Century – St. Louis, MO

June 10, 2000

By: Susanne Waite ( This e-mail address is being protected from spambots. You need JavaScript enabled to view it )

World-class doctors, researchers, scientists and individuals living with Kennedy’s from around the world met face-to-face for the first time at the Kennedy’s Symposium funded by the generosity of Nathaniel Ginor in memory of his beloved mother Dr. Zvia Ginor and coordinated by Dr. Diane Merry (Thomas Jefferson University, Philadelphia, PA).

Unfortunately, Dr. Fishbeck was unable to attend due to a family emergency. Dr. Diane Merry led the discussion in his absence.

Dr. Merry did a good job making the complex SBMA subject and medical terms simple and easy to understand. Kennedy’s disease is caused by a gene mutation in the androgen receptor which is located on the "X"-chromosome (primarily men are affected and show symptoms, women are carriers who pass the affected gene on to their sons). Women may be protected from the disease because they have two separate "X"-chromosomes (one carrying the Kennedy’s mutation and the other not) or perhaps protected because of lower testosterone levels. Researchers hope to model and find out why women carriers are protected from showing symptoms.

Dr. Merry discussed the genetic basis of SBMA (the expansion of a CAG repeat sequence in the androgen receptor gene), that this expanded DNA repeat is made into RNA and protein, and what is known about the unusual polyglutamine tract within the androgen receptor protein. This string of glutamine amino acids that is a part of the normal androgen receptor protein is much longer than it should be in Kennedy’s patients. What does this unusual mutation do to the protein? It is now known that the expanded glutamine stretch within the androgen receptor protein causes it to become toxic to motor neurons. The basis for this toxicity is unknown; all that is currently know about this toxic function is that the long glutamine tract causes the androgen receptor to fold in an abnormal way. Every protein in the cell must fold in a very particular way in order to function. The expansion of the glutamine tract causes the androgen receptor to misfold and to become very sticky. It forms large aggregated structures within neurons. It is still not known whether these sticky aggregates of protein are themselves bad or if they simply indicate that the androgen receptor is misfolded. There is probably some loss of androgen receptor function over time, which may cause some or all of the signs of androgen insensitivity (the breast enlargement, progressive loss of fertility, and testicular atrophy) that occur. However, this is likely secondary to the toxic gain of function that is caused by the misfolding of the protein. A high priority is to develop the experimental models in order to understand the dysfunction of the neurons and to understand some very basic questions about this androgen receptor mutation and how it specifically affects motor neurons. The neurons affected in Kennedy’s Disease are lower motor neurons of the spinal cord and brainstem. These brainstem neurons enervate the bulbar muscles that control chewing and swallowing. Thus, the involvement of spinal and bulbar muscles helps to distinguish Kennedy’s from SMA III.