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BackgroundPick’s disease (PiD) is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. PiD is pathologically defined by argyrophilic inclusion Pick bodies and ballooned neurons in the frontal and temporal brain lobes. PiD is characterised by the presence of Pick bodies which are formed from aggregated, hyperphosphorylated, 3-repeat tau proteins, encoded by theMAPTgene. TheMAPTH2 haplotype has consistently been associated with a decreased disease risk of the 4-repeat tauopathies of progressive supranuclear palsy and corticobasal degeneration, however its role in susceptibility to PiD is unclear. The primary aim of this study was to evaluate the association betweenMAPTH2 and risk of PiD.MethodsWe established the Pick’s disease International Consortium (PIC) and collected 338 (60.7% male) pathologically confirmed PiD brains from 39 sites worldwide. 1,312 neurologically healthy clinical controls were recruited from Mayo Clinic Jacksonville, FL (N=881) or Rochester, MN (N=431). For the primary analysis, subjects were directly genotyped forMAPTH1-H2 haplotype-defining variant rs8070723. In secondary analysis, we genotyped and constructed the six-variantMAPTH1 subhaplotypes (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521).FindingsOur primary analysis found that theMAPTH2 haplotype was associated with increased risk of PiD (OR: 1.35, 95% CI: 1.12-1.64 P=0.002). In secondary analysis involving H1 subhaplotypes, a protective association with PiD was observed for the H1f haplotype (0.0% vs. 1.2%, P=0.049), with a similar trend noted for H1b (OR: 0.76, 95% CI: 0.58-1.00, P=0.051). The 4-repeat tauopathy risk haplotypeMAPTH1c was not associated with PiD susceptibility (OR: 0.93, 95% CI: 0.70-1.25, P=0.65).InterpretationThe PIC represents the first opportunity to perform relatively large-scale studies to enhance our understanding of the pathobiology of PiD. This study demonstrates that in contrast to its protective role in 4R tauopathies, theMAPTH2 haplotype is associated with an increased risk of PiD. This finding is critical in directing isoform-related therapeutics for tauopathies.FundingSee funding section

BackgroundBi-allelic pathogenic variants inGBA1are the cause of Gaucher disease (GD1), a lysosomal storage disorder resulting from deficient glucocerebrosidase. HeterozygousGBA1variants are also a common genetic risk factor for Parkinson’s disease (PD). GD manifests with considerable clinical heterogeneity and is also associated with an increased risk of PD.ObjectiveTo investigate the contribution of PD risk variants to risk of PD in patients with GD1.MethodsWe studied 225 patients with GD1, including 199 without PD and 26 with PD. All cases were genotyped and the genetic data was imputed using common pipelines.ResultsOn average, patients with GD1 with PD have a significantly higher PD genetic risk score than those without PD (P=0.021).ConclusionsOur results indicate that variants included in the PD genetic risk score were more frequent in patients with GD1 who developed PD, suggesting that common risk variants may affect underlying biological pathways.Supplemental datahere

ImportanceThere is a pressing need to understand the biology of Parkinson’s disease (PD) progression and to identify biological pathways as possible therapeutic targets.ObjectiveTo identify genomic variation associated with PD motor presentation and early stage progression.DesignGWAS meta-analysis of early PD motor progression, from multiple longitudinal cohorts, using MDS-UPDRS III clinical assessments.SettingMulticentreParticipants3572 unrelated European ancestry individuals diagnosed with PD from 6 studies.Main Outcomes and MeasuresLinear mixed effect models under an additive model corrected for age at diagnosis, gender, and the first 5 genetic principal components (PCs), with axial, limb, and total MDS-UPDRS III as outcomes of the model.ResultsWe identified an association between the PD axial rate of progression and variation at theGJA5locus at 1q12 (Beta = -0.25, SE = 0.04,P= 3.4e-10). Exploration of the regulation of gene expression in the region (cis-eQTL analysis) showed that the lead variant was associated with expression ofACP6, a lysophosphatidic acid phosphatase that regulates mitochondrial lipid biosynthesis (cis-eQTLs p-values in blood and brain RNA expression datasets: < 10−8in eQTLGen and 10−7in PsychEncode). In addition, we found a nominal association between axial motor presentation and theMAD1L1gene at 7q21.11 (Beta = 0.54, SE = 0.11,P= 1.6e-7), a gene previously associated with neuropsychiatric disease, and in the long non-coding RNALINC00511at 17q21.31 (Beta = -0.62, SE = 0.11,P= 6.3e-8). Further functional annotation allowed us to nominate the likely causal variants and determine that variants at 7q21.11 may be related to dysregulation ofMAD1L1expression. Variants atLINC00511may cause a disruption of a distal epigenetic regulation ofSOX9through an anchored chromatin loop.Conclusions and RelevanceOur large multicentre study sheds new light on the genetic architecture of PD progression, which is distinct from PD susceptibility. Our study highlights the potential role of mitochondrial lipid homeostasis in the progression of PD, which may be important in establishing new drug targets to tackle disease progression.

BackgroundOpen science and collaboration are necessary to facilitate the advancement of Parkinson’s disease (PD) research. Hackathons are collaborative events that bring together people with different skill sets and backgrounds to generate resources and creative solutions to problems. These events can be used as training and networking opportunities.ObjectiveTo coordinate a virtual hackathon to develop novel PD research tools.Methods49 early career scientists from 12 countries collaborated in a virtual 3-day hackathon event in May 2021, during which they built tools and pipelines with a focus on PD. Resources were created with the goal of helping scientists accelerate their own research by having access to the necessary code and tools.ResultsEach team was allocated one of nine different projects, each with a different goal. These included developing post-genome-wide association studies (GWAS) analysis pipelines, downstream analysis of genetic variation pipelines, and various visualization tools.ConclusionHackathons are a valuable approach to inspire creative thinking, supplement training in data science, and foster collaborative scientific relationships, which are foundational practices for early career researchers. The resources generated can be used to accelerate research on the genetics of PD.

BackgroundPatients with Parkinson’s disease (PD) have variable disease progression. More accurate prediction of progression could improve clinical trial design. Although some variance in clinical progression can be predicted by age at onset and phenotype, we hypothesise that this can be improved by blood biomarkers.ObjectiveTo determine if serum neurofilament light (NfL) is a useful biomarker for prognostic modelling in PD.MethodsWe evaluated the relationship between serum NfL and baseline and longitudinal clinical measures as well as patients’ genetic (GBA and APOE) status in a large clinical dataset. We classified patients as having a favourable or an unfavourable outcome based on a previously validated model and explored whether serum NfL could distinguish prognostic phenotypes. We compared NfL with baseline candidate predictor variables and studied the combination of clinical, serum and genetic data.ResultsSerum NfL was associated with patients’ cognitive status at baseline. Baseline NfL was associated with the progression of motor and functional impairment and with increased mortality (Survival HR 1.85, CI: 1.03-3.33, p=0.04). Baseline NfL levels predicted unfavourable progression to a similar extent as previously validated clinical predictors (AUC: 0.74 vs 0.78, p=0.22). The combination of clinical, genetic and biomarker data produced a strong predication of unfavourable outcomes as compared to age and gender alone (AUC: 0.71-age/gender vs 0.83-ALL p = 0.0076)ConclusionsBaseline serum NfL provides an objective measure of neurodegeneration in PD patients. Clinical trials of disease-modifying therapies might usefully stratify patients according using clinical, genetic and NfL status at the time of recruitment.

Mutations in the TANK-binding kinase 1 (TBK1) gene have recently been shown to cause frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The phenotype is highly variable and has been associated with behavioral variant FTD, primary progressive aphasia, and pure ALS. We describe the clinical, anatomical, and pathological features of a patient who developed corticobasal syndrome (CBS)/progressive nonfluent aphasia (PNFA) overlap. The patient presented with progressive speech difficulties and later developed an asymmetric akinetic–rigid syndrome. Neuroimaging showed asymmetrical frontal atrophy, predominantly affecting the right side. There was a strong family history of neurodegenerative disease with four out of seven siblings developing either dementia or ALS in their 50s and 60s. The patient died at the age of 71 and the brain was donated for postmortem analysis. Histopathological examination showed frontotemporal lobar degeneration TDP-43 type A pathology. Genetic screening did not reveal a mutation in the GRN, MAPT, or C9orf72 genes, but exome sequencing revealed a novel p.E703X mutation in the TBK1 gene. Although segregation data were not available, this loss-of-function mutation is highly likely to be pathogenic because it is predicted to disrupt TBK1/optineurin interaction and impair cellular autophagy. In conclusion, we show that TBK1 mutations can be a cause of an atypical parkinsonian syndrome and screening should be considered in CBS patients with a family history of dementia or ALS.