What Causes Dystonia?
Most cases of dystonia do not have a specific cause. In some cases dystonia seems to be related to a chemical imbalance in the part of the brain known as the basal ganglia. That’s the area of the brain that is responsible for initiating muscle contractions and controlling movement.
In some cases dystonia occurs due to a known specific cause (acquired dystonia). Other cases are genetic and occur due to specific genetic mutations. Other cases occur randomly for no apparent reason, without a family history of the disorder (sporadically). In many cases, the exact-underlying cause of dystonia is unknown or unproven (idiopathic). Most likely, many cases of dystonia develop due to multiple factors including genetic and environmental ones.
Conditions associated with acquired dystonia include brain injury (particularly due to lack of oxygen) during or around the time of birth (perinatal period), certain infections, reactions to certain drugs, brain trauma, or various vascular abnormalities such as stroke, arteriovenous malformations, or profuse, excessive bleeding (haemorrhaging). Dystonia can also result from other illness affecting the central nervous system.
Multiple genes have been associated with inherited dystonia. Researchers are actively seeking to locate additional gene and gene markers. Genetic factors are also believed to play a role in idiopathic and acquired dystonia, especially in individuals who have a relative with another form of dystonia. These individuals may have a genetic susceptibility to developing the disorder. A person who is genetically predisposed to a disorder carries a gene (or genes)for the disease, but may not be expressed unless it is triggered or activated by other genetic modifiers or environmental factors (complex genetics).
We don’t know the cause of dystonia because scientists have not yet identified the precise biochemical process in the body that triggers the symptoms. This is often referred to as the “mechanism” of dystonia, and it is suspected that this mechanism is common to all forms of dystonia.
Research is ongoing to determine the specific roles that genetic, environmental and other factors ultimately play in the development of the disorder.