ABOUT KENNEDY’S DISEASE
What is Kennedy’s Disease?
Kennedy’s Disease, or X-linked motor neuron disease, is a rare inherited neuromuscular disorder also known as X-linked recessive bulbospinal neuropathy or X-linked spinal and bulbar atrophy.
It is an adult onset, progressive disorder, characterised by the degeneration of lower motor neurons within the spinal cord and brainstem. This causes progressive weakening and wasting of the muscles particularly in the arms and legs.
Humans have 46 paired chromosomes, with two sex chromosomes that decide gender and 44 chromosomes that dictate other factors. The mother’s egg always provides a female sex chromosome known as ‘X’, while the father’s sperm contributes either an ‘X’ (female) or ‘Y’ (male) chromosome. A pairing of ‘XX’ sex chromosomes means the baby is a girl, while ‘XY’ means the baby is a boy.
Kennedy’s disease is caused by a genetic mutation of the androgen receptor gene on the X chromosome.
Since the disease is recessive, the presence of the normal gene on the other X chromosome means that girls don’t develop the symptoms of disease, because the normal gene overrides the mutated one.
Girls will be carriers, and each son of a carrier mother has a 50 per cent chance of inheriting the gene and developing the disease. This is because boys only receive one X chromosome and, if that has the mutated gene, they will one day develop the symptoms of Kennedy’s disease.
It is estimated that 1 in 7,000 males have this genetic defect and because it is relatively rare, Kennedy’s Disease is often initially misdiagnosed or goes undiagnosed for years. There is no cure for Kennedy’s disease and no current treatment available.
Our partners at the Motor Neurone Association (MNDA) have prepared an excellent brochure on Kennedys Disease, please click here to download the brochure. The MNDA also has a remit to support people living with Kennedy’s Disease.
Our partners in France have prepared an excellent protocol for the management of Kennedy’s Disease, which has been universally acknowledged – please click here to download this protocol.
FACTS OF KD
It is a rare disease
There is no cure (yet!)
The defect is in the ‘X’ Chromosome
Generally it affects males
Women are carriers (in rare cases they can suffer mild symptoms)
The majority of research funding has been through private donations
LIVING WITH KD
Medications to reduce muscle cramps and tremors
Plenty of rest and avoidance of exhaustion
Healthy, balanced diet
Gentle and regular aerobic exercise
Regular stretching to help reduce muscle cramping
Pain management
Support from speech, occupational and physiotherapy
SYMPTOMS
Swallowing difficulties
Speech difficulties
Hand tremors
Absent reflexes
Low sperm count
Reduced sex drive
Muscle weakness, wastage, twitches, cramps and spasms
Shrunken testicles
Enlarged Breast tissue (gynaecomastia)
How is KD diagnosed?
There are various methods of diagnosis. Your GP can refer you to a neurologist in your area and they can take a definitive blood test to establish if you have the genetic defect that causes KD. Your neurologist can establish the likelihood of KD through a physical examination.
Who is affected by KD
Men suffer with KD, however, females can have mild symptoms.
When does KD kick in?
KD usually starts to affect people in the 30’s to 50’s. There have been earlier reported cases and later reported cases too.
Is the any medication to help with the offset of the disease?
Trials are currently underway for new treatments.