Myoclonic dystonia or Myoclonus dystonia syndrome is a rare movement disorder that induces spontaneous muscle contraction causing abnormal posture. The prevalence of myoclonus dystonia has not been reported, however, this disorder falls under the umbrella of movement disorders which affect thousands worldwide. Myoclonus dystonia results from mutations in the SGCE gene coding for an integral membrane protein found in both neurons and muscle fibers. Those suffering from this disease exhibit symptoms of rapid, jerky movements of the upper limbs (myoclonus), as well as distortion of the bodys orientation due to simultaneous activation of agonist and antagonist muscles (dystonia). Myoclonus dystonia is caused by loss-of-function-mutations in the epsilon sarcoglycan gene (SGCE). The disease is dominantly inherited, however SGCE is an imprinted gene, so only the paternal allele is expressed. Therefore, children suffering from this disease inherit the mutation from the father. If the mutated allele is inherited from the mother, the child is not likely to exhibit symptoms. While no cure has been found for myoclonus dystonia, treatment options are available to those suffering from the disease. Ethanol often ameliorates the symptoms well, and so the syndrome is also called "Alcohol-responsive dystonia". Alcohol may be substituted by benzodiazepines,  such as clonazepam, which work through the same mechanism. Deep brain stimulation (DBS) is another viable option that can alleviate symptoms without the unwanted side effects of medications, and has been successful in treating other movement disorders. Signs and symptoms
Myoclonus dystonia is characterized by two primary features: myoclonus and dystonia.
Acetylcholine is usually overactive in dystonia patients and blocking of this neurotransmitter would reduce contortion of the upper body, but can produce side effects of drowsiness, confusion and memory issues in adults. Botulinum toxin
Botulinum toxin injections also act upon acetylcholine to reduce dystonia symptoms. The neurotoxin is active in presynaptic terminals and blocks exocytosis of acetylcholine into the synaptic cleft which reduces muscle activity. Botulinum may also have a role in inhibiting glutamate and changing muscle movement. Studies have also shown possible axon transport of this neurotoxin as well as its function as a pain reliever without effect on overactive muscle movement in myoclonus dystonia patients. Alcohol
Consumption of alcohol has also been found to be an effective agent for temporarily easing the severity of the tremors associated with myoclonus dystonia. Alcohol causes an increase in GABA transmission between interneurons and Purkinje cells. This then reduces the transmission of glutamate at granule cell-Purkinje cell synapses, which decreases muscle movements. This treatment only alleviates the strength of the tremors for a short duration and does not change how often tremors will occur. Doctors inform patients of risks associated with the use of alcohol for myoclonus dystonia due to the high susceptibility for excessive alcohol use and dependency. Alcohol use disorder itself causes tremors in the hands and degeneration of the Purkinje cells and other parts of the cerebral cortex, counteracting alcohols original corrective effects.