MJD stands for Machado-Joseph Disease and is also known as Spinocerebellar Ataxia Type 3 (SCA3). MJD is a rare, inherited neurological disorder and is a progressive disease meaning symptoms get worse over time. MJD causes damage to part of the brain called the cerebellum and brainstem. This damage initially causes muscular weakness. It progresses over time to a total lack of voluntary control and very significant permanent physical disability.

One of MJD's main symptoms is ataxia. Ataxia is a general term meaning lack of muscle control or coordination. MJD is characterised by a slow, progressive clumsiness in the arms and legs, a staggering, lurching gait that can be mistaken for drunkenness, difficulty with speech and swallowing, impaired eye movements and lower limb spasticity. This  progresses to being wheelchair bound, unable to do simple activities of daily living and needing full time care.

Life expectancy ranges from the mid-30s, for those with the most severe forms of early onset MJD, to a nearly normal life expectancy for those with mild, late onset forms. The cause of death, for those who die early from the disease, is often aspiration pneumonia.

There is no treatment or cure for MJD!