Puschmann, Andreas

PolyQ ATXN3 is a pharmacodynamic marker for SCA3, and a SNP associated with the expanded allele may serve to specifically target mutant ATXN3 .

ABSTRACTBackground and Objectives: To study selective regional binding for tau pathology in vivo, using PET with [11C]PBB3 in PSP patients, and other conditions not typically associated with tauopathy.Methods: Dynamic PET scans were obtained for 70 minutes after the bolus injection of [11C]PBB3 in 5 PSP subjects, 1 subject with DCTN1 mutation and PSP phenotype, 3 asymptomatic SNCA duplication carriers, 1 MSA subject, and 6 healthy controls of similar age. Tissue reference Logan analysis was applied to each region of interest using a cerebellar white matter reference region.Results: In comparison to the control group, PSP subjects showed specific uptake of [11C]PBB3 in putamen, midbrain, GP, and SN. Longer disease duration and more advanced clinical severity were generally associated with higher tracer retention. A DCTN1/PSP phenotype case showed increased binding in putamen, parietal lobe, and GP. In SNCA duplication carriers, there was a significant increase of [11C] PBB3 binding in GP, putamen, thalamus, ventral striatum, SN, and pedunculopontine nucleus. The MSA case showed increased binding in frontal lobe, GP, midbrain, parietal lobe, putamen, temporal lobe, SN, thalamus, and ventral striatum.Conclusions: All PSP patients showed increased retention of the tracer in the basal ganglia, as expected. Binding was also present in asymptomatic SNCA duplication carriers and in an MSA case, which are not typically associated with pathological tau deposition. This suggests the possibility that [11C]PBB3 binds to alpha‐synuclein. © 2017 International Parkinson and Movement Disorder Society

BackgroundRecently, a novel mutation in exon 24 of DNAJC13 gene (p.Asn855Ser, rs387907571) has been reported to cause autosomal dominant Parkinson's disease (PD) in a multi‐incident Mennonite family.MethodsIn the present study the mutation containing exon of the DNAJC13 gene has been sequenced in a Caucasian series consisting of 1938 patients with clinical PD and 838 with pathologically diagnosed Lewy body disease (LBD).ResultsOur sequence analysis did not identify any coding variants in exon 24 of DNAJC13. Two previously described variants in intron 23 (rs200204728 and rs2369796) were observed.ConclusionOur results indicate that the region surrounding the DNAJC13 p.Asn855Ser substitution is highly conserved and mutations in this exon are not a common cause of PD or LBD among Caucasian populations.

ABSTRACT Objectives To determine whether α‐synuclein dinucleotide repeat (REP1) genotypes are associated with survival in Parkinson's disease (PD). Methods Investigators from the Genetic Epidemiology of Parkinson's Disease Consortium provided REP1 genotypes and baseline and follow‐up clinical data for cases. The primary outcome was time to death. Cox proportional hazards regression models were used to assess the association of REP1 genotypes with survival. Results Twenty‐one sites contributed data for 6,154 cases. There was no significant association between α‐synuclein REP1 genotypes and survival in PD. However, there was a significant association between REP1 genotypes and age at onset of PD (hazard ratio: 1.06; 95% confidence interval: 1.01‐1.10; P value = 0.01). Conclusions In our large consortium study, α‐synuclein REP1 genotypes were not associated with survival in PD. Further studies of α‐synuclein's role in disease progression and long‐term outcomes are needed. © 2014 International Parkinson and Movement Disorder Society

ABSTRACTBackgroundVariants within the leucine‐rich repeat kinase 2 gene are recognized as the most frequent genetic cause of Parkinson's disease. Leucine‐rich repeat kinase 2 variation related to disease susceptibility displays many features that reflect the nature of complex, late‐onset sporadic disorders like Parkinson's disease.MethodsThe Genetic Epidemiology of Parkinson's Disease Consortium recently performed the largest genetic association study for variants in the leucine‐rich repeat kinase 2 gene across 23 different sites in 15 countries.ResultsHerein, we detail the allele frequencies for the novel risk factors (p.A419V and p.M1646T) and the protective haplotype (p.N551K‐R1398H‐K1423K) nominated in the original publication. Simple population allele frequencies not only can provide insight into the clinical relevance of specific variants but also can help genetically define patient groups.ConclusionsEstablishing individual patient‐based genomic susceptibility profiles that incorporate both risk factors and protective factors will determine future diagnostic and treatment strategies. © 2013 International Parkinson and Movement Disorder Society