The Role of TOR1A Polymorphisms in Dystonia: A Systematic Review and Meta-Analysis
Vasileios Siokas1, Efthimios Dardiotis1, Evangelia E Tsironi2
1Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece.
Importance:
A number of genetic loci were found to be associated with dystonia. Quite a few studies have been contacted to examine possible contribution of TOR1A variants to the risk of dystonia, but their results remain conflicting. The aim of the present study was to systematically evaluate the effect of TOR1A gene SNPs on dystonia and its phenotypic subtypes regarding the body distribution.
Methods:
We performed a systematic review of Pubmed database to identify all available studies that reported genotype frequencies of TOR1A SNPs in dystonia. In total 16 studies were included in the quantitative analysis. Odds ratios (ORs) were calculated in each study to estimate the influence of TOR1A SNPs genotypes on the risk of dystonia. The fixed-effects model and the random effects model, in case of high heterogeneity, for recessive and dominant mode of inheritance as well as the free generalized odds ratio (ORG) model were used to calculate both the pooled point estimate in each study and the overall estimates.
Results:
Rs1182 was found to be associated with focal dystonia in recessive mode of inheritance [Odds Ratio, OR (95% confidence interval, C.I.): 1.83 (1.14-2.93), Pz = 0.01]. In addition, rs1801968 was associated with writer's cramp in both recessive and dominant modes [OR (95%C.I.): 5.99 (2.08-17.21), Pz = 0.00009] and [2.48 (1.36-4.51), Pz = 0.003) respectively and in model free-approach [ORG (95%C.I.): 2.58 (1.45-4.58)].
Conclusions:
Our meta-analysis revealed a significant implication of rs1182 and rs1801968 TOR1A variants in the development of focal dystonia and writer's cramp respectively. TOR1A gene variants seem to be implicated in dystonia phenotype.
Related Concept Videos
Directly Acting Muscle Relaxants: Dantrolene and Botulinum Toxin
The binding of dantrolene to the RYR1...
Classification of Skeletal Muscle Relaxants
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...
Peripherally and Centrally Acting Muscle Relaxants: A Comparison
Centrally acting muscle relaxants can be further divided into spasmolytic and antispasmodic drugs. Spasmolytic...
Skeletal Muscle Relaxants: Therapeutic Uses
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase


