In contrast, ʟ-DOPA, which is not usually effective for the treatment of DYT1dystonia, did not increase dopamine release in either Dyt1 or control mice.
Interestingly, mutations in the TOR1A gene (the gene encoding torsinA) are associated with DYT1dystonia and with the preferential localization of mutated torsinA at the NE, where it is associated with lamina-associated polypeptide 1.
This review will summarize our current knowledge on the molecular and basic biological features of torsinA and its dysfunction when carrying disease-causing mutation, identifying future research priorities and proposing a model of dystonia pathogenesis that might extend beyond DYT1.
DYT1dystonia is a neurological disease caused by a dominant mutation that results in the loss of a glutamic acid in the endoplasmic reticulum-resident protein torsinA.
We also outline our experimental work in DYT1dystonia, a group of patients that share a genetically homogenous etiology and can be considered a prototypical dystonic disorder.
We observed a spectrum of clinical manifestations in KMT2B variant carriers, ranging from generalized dystonia to short stature or intellectual disability alone, even within the same family.
The mutations in patients 2 and 3 (c.3602dupC, p.M1202Dfs*22; c.4229delA, p.Q1410Rfs*12) lead to predicted unstable transcripts, likely to be subject to degradation by non-sense mediated decay.Childhood-onset progressive dystonia with orofacial involvement is one of the main clinical manifestations of KMT2B mutations.
GNAL loss-of-function mutations are causally-associated with isolated dystonia, a movement disorder characterized by involuntary muscle contractions leading to abnormal postures.
These findings suggest distinct pathogenetic mechanisms between manif-DYT1 vs. non-manif-DYT1 and manif-non-DYT1 dystonia, especially in terms of possible nigral dopaminergic abnormalities.
These data introduce targets for future studies to identify which are causative and which are compensatory in DYT1dystonia, and thereby aid in defining appropriate therapies.
We used a multidisciplinary approach to investigate the responses to mu activation in 2 mouse models of DYT1dystonia (Tor1a<sup>+/Δgag</sup> mice, Tor1a<sup>+/-</sup> torsinA null mice, and their respective wild-types).
There are well-known monogenic forms of isolated dystonia with pediatric onset such as DYT1 and DYT6 transmitted with autosomal dominant inheritance and low penetrance.
We further expand the phenotypic spectrum of KMT2B-related disorders and show that some individuals can have severe developmental delay without dystonia at least until mid-childhood.