About dystonia Types of dystonia What are the causes? When generalised dystonia is inherited, the condition is caused by mutations in a specific gene. The gene abnormality causes a problem with the brain’s production of the chemical dopamine. Generalised dystonia is sometimes caused by a fault in the DYT1 gene. There are a number of other genes which cause primary early-onset generalised dystonia including the DYT5 gene which causes a rare type of generalised dystonia highly responsive to treatment by dopamine called dopa-responsive dystonia. If no genetic cause can be identified, the physician will explore if the dystonia is ‘acquired’. This may involve a MRI scan of the brain and testing for other rare conditions such as: Wilson’s disease - a treatable genetic condition in which the body does not process copper properly or; Neuronal brain iron accumulation syndrome (NBIA) – a genetic degenerative condition in which iron is deposited in the basal ganglia In idiopathic generalised dystonia there is no detectable abnormality on any brain scans or investigations so it is uncertain why the dystonia has appeared.