Mutational spectrum of GNAL, THAP1 and TOR1A genes in isolated dystonia: study in a population from Spain and systematic literature review.

OBJECTIVE: We aimed to investigate the prevalence of TOR1A, GNAL and THAP1 variants as the cause of dystonia in a cohort of Spanish patients with isolated dystonia and in the literature. METHODS: A population of 2028 subjects (including 1053 patients with different subtypes of isolated dystonia and 975 healthy controls) from southern and central Spain was included. The genes TOR1A, THAP1 and GNAL were screened using a combination of high-resolution melting analysis and direct DNA resequencing. In addition, an extensive literature search to identify original articles (published before 10 August 2020) reporting mutations in TOR1A, THAP1 or GNAL associated to dystonia was performed. RESULTS: Pathogenic or likely pathogenic variants in TOR1A, THAP1 and GNAL were identified in 0.48%, 0.57% and 0.29% of our patients, respectively. Five patients carried the variation p.Glu303del in TOR1A. A very rare variant in GNAL (p.Ser238Asn) was found as a putative risk factor for dystonia. In the literature, variations in TOR1A, THAP1 and GNAL accounted for about 6%, 1.8% and 1.1% of published dystonia patients, respectively. CONCLUSIONS: There is a different genetic contribution to dystonia of these three genes in our patients (about 1.3% of patients) and in the literature (about 3.6% of patients), probably due the high proportion of adult-onset cases in our cohort. As regards age at onset, site of dystonia onset, and final distribution, in our population there is a clear differentiation between DYT-TOR1A and DYT-GNAL, with DYT-THAP1 likely to be an intermediate phenotype.

Lack of validation of variants associated with cervical dystonia risk: a GWAS replication study.

BACKGROUND: A recent genome-wide association study (GWAS) has identified a putative association, not statistically confirmed, of cervical dystonia within several regions in a British population. Hence, the authors proposed dysfunction of the ion channel NALCN (for sodium leak channel, nonselective) as a plausible cause of cervical dystonia. The objective of our study was to investigate the association of five single nucleotide polymorphisms (SNPs) previously reported with high signals as putative genetic risk factors for cervical dystonia in a British GWAS, including two located in the NALCN gene region. METHODS: We performed a case-control association study in a Spanish population. The SNPs selected for genotyping were two SNPS in the NALCN gene (rs61973742 and rs1338041), one SNP in the OR4X2 gene (rs67863238), one SNP in the COL4A1 region (rs619152), and one intergenic SNP (rs1249277). Genomic DNA was collected from 252 patients with cervical dystonia, with a mean age of 55.3 ± 14.1 years (mean age at onset, 43.5 ± 15.7 years), and 342 unrelated control subjects with a mean age of 56.3 ± 14.3 years. Genotyping of SNPs was performed using TaqMan assays and SimpleProbe assays. RESULTS: The SNP rs619152 had to be excluded because of assay failure. No significant differences were found in allele distribution between cases and controls for all analyzed SNPs. Therefore, we found no association with cervical dystonia for the analyzed SNPs in our Spanish population. CONCLUSIONS: We did not find any evidence supporting the association of NALCN with cervical dystonia, indicating that this gene is not implicated in the pathogenesis of this disorder in our cervical dystonia population.

BDNF Val66Met polymorphism in primary adult-onset dystonia: a case-control study and meta-analysis.

BACKGROUND: A polymorphism in brain-derived neurotrophic factor (BDNF) (Val66Met) has been reported as a risk factor in primary dystonia. However, overall the results have been inconclusive. Our aim was to clarify the association of Val66Met with primary dystonia, and with the most prevalent clinical subtypes, cervical dystonia and blepharospasm. METHODS: We conducted a Spanish multicenter case-control study (including 680 primary dystonia patients and 788 healthy controls) and performed a meta-analysis integrating our study and six previously published studies (including a total of 1,936 primary dystonia patients and 2,519 healthy controls). RESULTS: We found no allelic or genotypic association with primary dystonia, cervical dystonia, or blepharospasm risks, for the allele A (Met) from a BDNF Val66Met polymorphism in our case-control study. This was confirmed by results from our meta-analysis in white and mixed ethnic populations in any genetic model. CONCLUSION: We did not find any evidence supporting the association of the BDNF Val66Met polymorphism with primary dystonia.

Does Your Loved One With Cognitive Symptoms Need to See a Doctor? Check It Online.

Widespread access to emerging information and communication technologies (ICT) allows its use for the screening of diseases in the general population. At the initiative of the Spanish Confederation of Associations of Families of People with Alzheimer's disease and other dementias (CEAFA), a website (http://www.problemasmemoria.com) has been created that provides information about Alzheimer's disease and includes questionnaires to be completed by family or friends concerned about memory problems of a relative. A cross-sectional, randomized, multicenter study was performed to evaluate feasibility, validity, and user satisfaction with an electronic method of completion vs. the current method of paper-based questionnaires for clinically dementia screening completed by the informants: the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) and the Alzheimer's disease-8 screening test (AD8). A total of 111 pairs were recruited by seven memory clinics. Informants completed IQCODE and AD8 questionnaires both in their paper and electronic versions. The correlation between paper and electronic versions was significantly positive for IQCODE (r = 0.98; p < 0.001) and AD8 (r = 0.96; p < 0.001). The execution time did not differ significantly, and participants considered their use equally easy. This study shows that an electronic version of the IQCODE and AD8 questionnaires is suitable for its online use via the internet and achieves the same results as the traditional paper versions.

Acetylcholinesterase inhibitors and the risk of hip fracture in Alzheimer's disease patients: a case-control study.

Recent studies have reported the presence of acetylcholine (ACh) receptor subtypes in bone tissue, and have demonstrated that inhibition of the ACh receptors has negative effects on bone mass and fracture healing capacity. However, little is known about the potential clinical effects that increased ACh signaling might have on bone. Accordingly, this study was designed to determine whether the use of acetylcholinesterase inhibitors (AChEIs), a group of drugs that stimulate ACh receptors and are used to treat Alzheimer's disease (AD), is associated with a decreased risk of hip fracture in AD patients. To accomplish this objective, a case-control analysis was performed using the AD population, aged above 75 years, based in the local health area of the Carlos Haya Hospital, in Malaga, Spain. The cases were 80 AD patients that suffered a hip fracture between January 2004 and December 2008. The controls were 2178 AD patients without hip fracture followed at our health care area during the same period of time. Compared with patients who did not use AChEIs, the hip fracture adjusted odds ratio (OR) for users of AChEIs was 0.42 (95% confidence interval [CI], 0.24-0.72), for users of rivastigmine was 0.22 (95% CI, 0.10-0.45), and for users of donepezil was 0.39 (95% CI, 0.19-0.76). Data were adjusted for the following parameters: body mass index, fall risk, smoking habits, cognition, dependence, degree of AD, comorbidity score, treatment with selective serotonin reuptake inhibitors, age, and gender. Our data suggests that use of AChEIs donepezil and rivastigmine is associated with a reduced risk of fractures in AD patients. Many elderly patients with AD disease who are at risk of developing osteoporosis may potentially benefit from therapy with the AChEIs donepezil and rivastigmine.