Machado Joseph disease is a genetic disorder affecting muscle movement and development. Unlike many other genetic diseases, only one parent needs to carry the gene to pass the condition onto children. If one parent has the Machado Joseph disease (MJD) gene, children have a 50% chance of having the condition. The condition was first recognized in 1972. The name is attributed to two men with the condition – William Machado and Antone Joseph.
Researchers later discovered that Spinocerebellar Ataxia Type 3 (SCA3) was the same condition as MJD.
Who is at Risk?
Machado Joseph disease is most common in Portuguese and Azorean populations. SCA3 is found in all populations.
Symptoms of Machado Joseph disease are all associated with muscle movements. Common symptoms include:
- Irregular muscle movements
- Difficulty speaking
- Difficulty swallowing
- Weight loss
- Weakness in limbs
- Sporadic eye movements
Machado Joseph disease is a progressive disorder. Complications are often associated with the age when symptoms begin. In cases where patient diagnosis occurs much later in life, complications are minimal with death occurring from natural causes.
If symptoms appear early in life, complications may include inability to walk, recurrent pneumonia and memory loss. Most early deaths are associated with pneumonia.
The first step in diagnosing Machado Joseph disease is family history. If a member of the family has the condition, a genetic test may be ordered to rule out MJD. If there is no family history of MJD, diagnosis may be a long, drawn-out process of elimination. MJD is a rare condition, so doctors do not typically assume the condition if there is no family history. Genetic testing is the only means of definitively diagnosing MJD.
There is no cure for MJD, but symptoms are treatable. If patients present with symptoms similar to Parkinson’s disease, Levodopa may be prescribed. Other treatments include corrective lenses to correct reduced vision, mobility aids and speech therapy. As symptoms arise, medications are typically prescribed for sleep problems, muscle twitching, urinary dysfunction and cramping.
Life expectancy for patients with MJD and SCA3 differ. The condition ranges from mild to severe and symptoms can present very early in life up to 70 years of age. Many patients with MJD have a normal lifespan, but severe cases of the disorder can result in early death. Patients with severe MJD may live to the mid 30s.
READ ABOUT OTHER JEWISH GENETIC DISEASES