While the genetic cause of<unk>  is known, the mechanism by which it works is not fully known. Current research has provided promising results that may lead to a confirmation of the mechanism. This research has been performed on mice with the gene for producing cystatin B removed, to provide a similar set of symptoms to individuals with ULD. The mechanism currently supported by research is very similar to another theory of epilepsy progression known as kindling. Onset Current research links cystatin B to production of inhibitory neurons known as GABAergic neurons. It has shown that a lack of cystatin B due to a mutation of the CSTB gene leads to a decrease in the number of inhibitory neurons, and this lack of inhibition makes the cells in the brain, particularly the hippocampus, more excitable. It is hypothesized that this increase in excitability is what causes the myoclonic jerks and tonic-clonic seizures in patients with ULD. Progression Research also gives evidence to support the idea that cystatin B may be a type of "protecting" molecule in the brain. Normally, after a seizure, the presence of cystatin B prevents the neurons from dying due to toxic levels of neurotransmitters. Studies suggest that the absence of cystatin B leads to the death of affected neurons, leading to a damaged portion of the brain. This damage coupled with the increased excitability of the cells then leads to more damage, which is what makes<unk>  progressive.
Unverricht–Lundborg disease
Brill–Zinsser disease
Cruveilhier–Baumgarten disease
Letterer–Siwe disease
Paget–Schroetter disease
Tornwaldt's disease
Fox–Fordyce disease
Urbach–Wiethe disease