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We aimed to detail language profiles, brain metabolic patterns and proportion of Alzheimer's disease biomarkers in a cohort of patients with mixed primary progressive aphasia (mPPA). We considered 58 patients with PPA: 10 with non-fluent/agrammatic variant (nfvPPA), 16 with semantic variant (svPPA), 21 with logopenic variant (lvPPA) and 9 with mPPA. Patients with mPPA were further classified as 4 nf/lvPPA (with prevailing features for nfvPPA and lvPPA) and 5 s/lvPPA (with prevailing features for svPPA and lvPPA). Nf/lvPPA patients were characterized by higher proportion of Naming impairment compared to nfvPPA and more frequent Grammatical Errors and Phonologic Errors than lvPPA. S/lvPPA had higher proportion of impairment in Sentences Repetition compared to svPPA and in Single-word Comprehension compared to lvPPA. 100% of nf/lvPPA and 40% of s/lvPPA had Aβ positive biomarkers. Brain hypometabolic pattern in Nf/lvPPA was consistent with lvPPA, while s/lvPPA had a brain metabolism resembling svPPA. We concluded that nf/lvPPA patients might be considered as PPA variant due to Alzheimer's disease and s/lvPPA group mainly included patients with svPPA.

Presenilin1 (PSEN1) gene is the most common known genetic cause of early-onset familial Alzheimer's disease. We describe an Italian family with the known p.Ala260Gly mutation in PSEN1 gene. The presence of an asymptomatic 64-year-old male carrying the mutation provides evidence of a possible incomplete penetrance leading to a wider range of age at onset. In order to evaluate whether or not epigenetic modifications could contribute to the phenotypic heterogeneity, we assessed global DNA methylation levels which resulted significantly higher in the three females than in their presymptomatic brother. The study suggests that DNA methylation can contribute to slowing down or possibly protecting from the manifestation of symptoms even in monogenic diseases, emphasizing the great complexity of familial Alzheimer's disease.

The G4C2-repeat expansion in C9orf72 is the most common cause of frontotemporal dementia and of amyotrophic lateral sclerosis. The variability of age at onset and phenotypic presentations is a hallmark of C9orf72 disease. In this study, we aimed to identify modifying factors of disease onset in C9orf72 carriers using a family-based approach, in pairs of C9orf72 carrier relatives with concordant or discordant age at onset. Linkage and association analyses provided converging evidence for a locus on chromosome Xq27.3. The minor allele A of rs1009776 was associated with an earlier onset (P = 1 × 10−5). The association with onset of dementia was replicated in an independent cohort of unrelated C9orf72 patients (P = 0.009). The protective major allele delayed the onset of dementia from 5 to 13 years on average depending on the cohort considered. The same trend was observed in an independent cohort of C9orf72 patients with extreme deviation of the age at onset (P = 0.055). No association of rs1009776 was detected in GRN patients, suggesting that the effect of rs1009776 was restricted to the onset of dementia due to C9orf72. The minor allele A is associated with a higher SLITRK2 expression based on both expression quantitative trait loci (eQTL) databases and in-house expression studies performed on C9orf72 brain tissues. SLITRK2 encodes for a post-synaptic adhesion protein. We further show that synaptic vesicle glycoprotein 2 and synaptophysin, two synaptic vesicle proteins, were decreased in frontal cortex of C9orf72 patients carrying the minor allele. Upregulation of SLITRK2 might be associated with synaptic dysfunctions and drives adverse effects in C9orf72 patients that could be modulated in those carrying the protective allele. How the modulation of SLITRK2 expression affects synaptic functions and influences the disease onset of dementia in C9orf72 carriers will require further investigations. In summary, this study describes an original approach to detect modifier genes in rare diseases and reinforces rising links between C9orf72 and synaptic dysfunctions that might directly influence the occurrence of first symptoms.

Background Primary progressive aphasia (PPA) has been described as a neurodegenerative language disorder mainly affecting the left hemisphere. Few cases of right hemisphere damage in right-handed PPA subjects have been reported. This condition, named crossed aphasia in dextral (CAD), is relatively rare and probably related to an alteration during neurodevelopment of language networks. Objective To explore the prevalence of CAD in an Italian cohort of 68 PPA patients, in order to evaluate whether right hemisphere language lateralization could be a risk factor for PPA. Methods Clinical-demographic and cerebral [18F]-fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) scan were analyzed, resulting in 23 logopenic variant (lvPPA) patients, 26 non-fluent variant (nfvPPA) patients, and 19 semantic variant (svPPA) patients. SPM single subject routine was performed for diagnostic purposes in order to identify the hypometabolic pattern of each patient. Based on brain metabolic profile, PPA patients were divided in right and left lvPPA, nfvPPA, and svPPA. [18F]FDG-PET group analyses were performed with SPM two-sample t-test routine. Results 26% of lvPPA cases were identified as CAD based on right hypometabolic pattern. CAD patients did not differ from left lvPPA regarding demographic features and general cognitive performance; however, they performed better in specific working memory tasks and showed brain hypometabolism limited to the superior, middle, and supramarginal temporal gyri. Conclusion Atypical lateralization of language function could determine a vulnerability of the phonological language loop and in that way could be a risk factor for lvPPA.

Brain-derived natriuretic factor (BDNF) Val66Met polymorphism has been frequently reported to be associated with Alzheimer's disease (AD) with contrasting results. Numerous studies showed that Met allele increased the risk of AD only in women, while other studies have found worse cognitive performance in Val/Val carriers. We aimed to inquire the effects of Val66Met polymorphism on the progression from subjective cognitive decline (SCD) to mild cognitive impairment (MCI) and from MCI to AD and to ascertain if this effect is modulated by demographic and cognitive variables. For this purpose, we followed up 74 subjects (48 SCD, 26 MCI) for a mean time of 9 years. All participants underwent extensive neuropsychological assessment, cognitive reserve estimation, BDNF and apolipoprotein E (ApoE) genotype analysis at baseline. Personality traits and leisure activities were assessed in a subgroup. Each patient underwent clinical-neuropsychological follow-up, during which 18 out of 48 SCD subjects progressed to MCI and 14 out of 26 MCI subjects progressed to AD. We found that Val66Met increased the risk of progression from SCD to MCI and from MCI to AD only in women. Nevertheless, Val/Val carriers who progressed from SCD to MCI had a shorter conversion time compared to Met carriers. We concluded that Val66Met polymorphism might play different roles depending on sex and stage of the disease.

Frontotemporal dementia (FTD) is a clinical, genetic, and pathologic heterogeneous group of neurodegenerative diseases. In this study, we investigated the role of APOƐ4, rs5848 in GRN, and rs1042522 in TP53 gene as disease risk factors and/or phenotype modifiers in 440 FTD patients, including 175 C9orf72 expansion carriers. We found that the C9orf72 expansion carriers showing an earlier age at onset (p < 0.001). Among the clinical groups, the FTD-MND (motoneuron disease) showed the lowest survival (hazard ratio [HR] = 4.12), and the progressive nonfluent aphasia group showed the highest onset age (p = 0.03). In our cohort, the rs1042522 in TP53 was associated with disease onset (p = 0.02) and survival (HR = 1.73) and rs5848 GRN with a significantly shorter survival in CC homozygous patients (HR = 1.98). The frequency of APOƐ4 carriers was significantly increased in the C9orf72 noncarriers (p = 0.022). Although validation of our findings is necessary, our results suggest that TP53, GRN, and APOE genes may act as phenotype modifiers in FTD and should be considered in future clinical trials.

Background: The etiology of frontotemporal dementia (FTD) is poorly understood. To identify genes with predicted expression levels associated with FTD, we integrated summary statistics with external reference gene expression data using a transcriptome-wide association study approach. Methods: FUSION software was used to leverage FTD summary statistics (all FTD: n = 2154 cases, n = 4308 controls; behavioral variant FTD: n = 1337 cases, n = 2754 controls; semantic dementia: n = 308 cases, n = 616 controls; progressive nonfluent aphasia: n = 269 cases, n = 538 controls; FTD with motor neuron disease: n = 200 cases, n = 400 controls) from the International FTD-Genomics Consortium with 53 expression quantitative loci tissue type panels (n = 12,205; 5 consortia). Significance was assessed using a 5% false discovery rate threshold. Results: We identified 73 significant gene–tissue associations for FTD, representing 44 unique genes in 34 tissue types. Most significant findings were derived from dorsolateral prefrontal cortex splicing data (n = 19 genes, 26%). The 17q21.31 inversion locus contained 23 significant associations, representing 6 unique genes. Other top hits included SEC22B (a gene involved in vesicle trafficking), TRGV5, and ZNF302. A single gene finding (RAB38) was observed for behavioral variant FTD. For other clinical subtypes, no significant associations were observed. Conclusions: We identified novel candidate genes (e.g., SEC22B) and previously reported risk regions (e.g., 17q21.31) for FTD. Most significant associations were observed in dorsolateral prefrontal cortex splicing data despite the modest sample size of this reference panel. This suggests that our findings are specific to FTD and are likely to be biologically relevant highlights of genes at different FTD risk loci that are contributing to the disease pathology.

Background: Discordance among amyloid biomarkers is a challenge to overcome in order to increase diagnostic accuracy in dementia. Objectives: 1) To verify that cerebrospinal fluid (CSF) Aβ42/Aβ40 ratio (AβR) better agrees with Amyloid PET (Amy-PET) results compared to CSF Aβ42; 2) to detect differences among concordant positive, concordant negative, and discordant cases, basing the concordance definition on the agreement between CSF AβR and Amy-PET results; 3) to define the suspected underlying pathology of discordant cases using in vivo biomarkers. Method: We retrospectively enrolled 39 cognitively impaired participants in which neuropsychological tests, apolipoprotein E genotype determination, TC/MRI, FDG-PET, Amy-PET, and CSF analysis had been performed. In all cases, CSF analysis was repeated using the automated Lumipulse method. In discordant cases, FDG-PET scans were evaluated visually and using automated classifiers. Results: CSF AβR better agreed with Amy-PET compared to CSF Aβ42 (Cohen’s K 0.431 versus 0.05). Comparisons among groups did not show any difference in clinical characteristics except for age at symptoms onset that was higher in the 6 discordant cases with abnormal CSF AβR values and negative Amy-PET (CSF AβR+/AmyPET–). FDG-PET and all CSF markers (Aβ42, AβR, p-Tau, t-Tau) were suggestive of Alzheimer’s disease (AD) in 5 of these 6 cases. Conclusion: 1) CSF AβR is the CSF amyloid marker that shows the better level of agreement with Amy-PET results; 2) The use of FDG-PET and CSF-Tau markers in CSFAβR+/Amy-PET–discordant cases can support AD diagnosis; 3) Disagreement between positive CSF AβR and negative Amy-PET in symptomatic aged AD patients could be due to the variability in plaques conformation and a negative Amy-PET scan cannot be always sufficient to rule out AD.

Funder: QingLan Research Project of Jiangsu for Outstanding Young Teachers, Funder: Project funded by Postdoctoral Science Foundation of Xuzhou Medical University, Funder: Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) for Xuzhou Medical University, We employed Mendelian randomization (MR) to evaluate the causal relationship between leukocyte telomere length (LTL) and amyotrophic lateral sclerosis (ALS) with summary statistics from genome-wide association studies (n = ~ 38,000 for LTL and ~ 81,000 for ALS in the European population; n = ~ 23,000 for LTL and ~ 4,100 for ALS in the Asian population). We further evaluated mediation roles of lipids in the pathway from LTL to ALS. The odds ratio per standard deviation decrease of LTL on ALS was 1.10 (95% CI 0.93–1.31, p = 0.274) in the European population and 0.75 (95% CI 0.53–1.07, p = 0.116) in the Asian population. This null association was also detected between LTL and frontotemporal dementia in the European population. However, we found that an indirect effect of LTL on ALS might be mediated by low density lipoprotein (LDL) or total cholesterol (TC) in the European population. These results were robust against extensive sensitivity analyses. Overall, our MR study did not support the direct causal association between LTL and the ALS risk in neither population, but provided suggestive evidence for the mediation role of LDL or TC on the influence of LTL and ALS in the European population.

Background and purpose CLOCK and PER2 genes have been implicated in sleep-wake cycle alterations and neurodegenerative diseases. Our aim was to evaluate the effect of CLOCK T3111C and PER2 C111G on cognitive functioning in subjective cognitive decline (SCD) patients and mild cognitive impairment (MCI) patients at the baseline of a longitudinal study, and the effect of these two polymorphisms on the progression to Alzheimer's disease (AD) of the two groups. Methods Sixty-eight subjects (41 SCD and 27 MCI) who underwent clinical evaluation, neuropsychological assessment, CLOCK and PER2 genotyping at baseline and neuropsychological follow-up every 2 years for a mean time of 10 years were included. Subjects who developed AD (SCD-c and MCI-c) and non-converters (SCD-nc, MCI-nc) were considered. Results CLOCK T3111C was detected in 47% of cases (21 SCD, 11 MCI) and PER2 C111G in 19% of cases (eight SCD and five MCI). PER2 G carriers presented lower premorbid intelligence score (P = 0.049), fewer years of education (P = 0.007) and a lower frequency of family history of AD (P = 0.04) than G non-carriers. MCI PER2 G carriers had worse performance in tests assessing memory, executive function, language and visuospatial abilities at baseline. During follow-up, two SCD and 15 MCI subjects progressed to AD: both of the SCD-c subjects presented the PER2 G allele, while none of the SCD PER2 G non-carriers converted to AD (P = 0.003). Conclusion PER2 seems to have a role in cognitive reserve and cognition in SCD and MCI patients. Nevertheless, further studies are needed to assess the role of PER2 C111G on the risk of progression to AD.

Background: Some genes could interact with cardiovascular risk factors in the development of Alzheimer’s disease. We aimed to evaluate the interaction between ApoE ε4 status, Clock T3111C and Per2 C111G polymorphisms with cardiovascular profile in Subjective Cognitive Decline (SCD) and Mild Cognitive Impairment (MCI). Methods: We included 68 patients who underwent clinical evaluation; neuropsychological assessment; ApoE, Clock and Per2 genotyping at baseline; and neuropsychological follow-up every 12–24 months for a mean of 13 years. We considered subjects who developed AD and non-converters. Results: Clock T3111C was detected in 47% of cases, Per2 C111G in 19% of cases. ApoE ε4 carriers presented higher risk of heart disease; Clock C-carriers were more frequently smokers than non C-carriers. During the follow-up, 17 patients progressed to AD. Age at baseline, ApoE ε 4 and dyslipidemia increased the risk of conversion to AD. ApoE ε4 carriers with history of dyslipidemia showed higher risk to convert to AD compared to ApoE ε4− groups and ApoE ε4+ without dyslipidemia patients. Clock C-carriers with history of blood hypertension had a higher risk of conversion to AD. Conclusions: ApoE and Clock T3111C seem to interact with cardiovascular risk factors in SCD and MCI patients influencing the progression to AD.

Background: Some genes could interact with cardiovascular risk factors in the development of Alzheimer&rsquo, s disease. We aimed to evaluate the interaction between ApoE &epsilon, 4 status, Clock T3111C and Per2 C111G polymorphisms with cardiovascular profile in Subjective Cognitive Decline (SCD) and Mild Cognitive Impairment (MCI). Methods: We included 68 patients who underwent clinical evaluation, neuropsychological assessment, ApoE, Clock and Per2 genotyping at baseline, and neuropsychological follow-up every 12&ndash, 24 months for a mean of 13 years. We considered subjects who developed AD and non-converters. Results: Clock T3111C was detected in 47% of cases, Per2 C111G in 19% of cases. ApoE &epsilon, 4 carriers presented higher risk of heart disease, Clock C-carriers were more frequently smokers than non C-carriers. During the follow-up, 17 patients progressed to AD. Age at baseline, ApoE &epsilon, 4 and dyslipidemia increased the risk of conversion to AD. ApoE &epsilon, 4 carriers with history of dyslipidemia showed higher risk to convert to AD compared to ApoE &epsilon, 4&minus, groups and ApoE &epsilon, 4+ without dyslipidemia patients. Clock C-carriers with history of blood hypertension had a higher risk of conversion to AD. Conclusions: ApoE and Clock T3111C seem to interact with cardiovascular risk factors in SCD and MCI patients influencing the progression to AD.

An early differentiation between Alzheimer’s Disease (AD) and other dementias is crucial for an adequate patients’ management, albeit it may result difficult for the occurrence of “atypical presentations.” Current diagnostic criteria recognize the importance of biomarkers for AD diagnosis, but still an optimal diagnostic work-up isn’t available. Evaluate the utility and reproducibility of biomarkers and propose an “optimal” diagnostic work-up in atypical dementia. (1) a retrospective selection of “atypical dementia cases”; (2) a repetition of diagnostic assessment by two neurologists following two different diagnostic work-ups, each consisting of multiple steps; (3) a comparison between diagnostic accuracy and confidence reached at each step by both neurologists and evaluation of the inter-rater agreement. In AD, regardless of the undertaken diagnostic work-up, a significant gain in accuracy was reached by both neurologists after the second step, whereas in frontotemporal dementia (FTD), adding subsequent steps was not always sufficient to increase significantly the baseline accuracy. A relevant increment in diagnostic confidence was detectable after studying pathophysiological markers in AD, and after assessing brain metabolism in FTD. The inter-rater agreement was higher at the second step for the AD group when the pathophysiological markers were available and for the FTD group when the results of FDG-PET were accessible. In atypical cases of dementia, biomarkers significantly raise diagnostic accuracy, confidence, and agreement. This study introduces a proof of diagnostic work-up that combines imaging and CSF biomarkers and suggests distinct ways to proceed on the basis of a greater diagnostic likelihood.

Studies on the genetics of Alzheimer's disease (AD) have revealed the complexity and heterogeneity of the disease. All our studies have supported this evidence and contribute to the current understanding of the genetic architecture of AD. This report reviews the success of our investigations, focusing on the implications and importance of the genetics of AD, and demonstrates the relevance of research strategies embracing partnerships.

BACKGROUND AND PURPOSE Subjective cognitive decline (SCD) is a self-experienced decline in cognitive capacity with normal performance on standardized cognitive tests and has been shown to increase the risk of Alzheimer's disease (AD). SCD could also be related to other conditions such as normal aging, psychiatric, neurological or medical disorders. The SCD Initiative proposed a set of features (SCD-plus) that increase the likelihood of preclinical AD in individuals with SCD. Our aim was to assess the effect of these features on the risk of conversion from SCD to AD. METHODS In total 150 SCD subjects who underwent extensive neuropsychological investigation, assessment of cognitive complaints and apolipoprotein E (ApoE) genotyping at baseline and clinical-neuropsychological follow-up for a mean time of 11 years were included. RESULTS During the follow-up, 20 subjects developed AD. Considering SCD-plus features, age at onset ≥60 years and ApoE e4 significantly increased the risk of conversion from SCD to AD. When our sample was stratified into three groups (no risk factor, one risk factor, two risk factors), the proportion of conversion was statistically significantly different between the three groups. CONCLUSIONS Our model allows the risk of AD to be stratified in patients experiencing SCD according to age at onset and ApoE genotype.

We analyzed the frequency of intermediate alleles (IAs) in the ATXN1, ATXN2, and HTT genes in several neurodegenerative diseases. The study included 1126 patients with Alzheimer's disease (AD), 440 patients with frontotemporal dementia (FTD), and 610 patients with Parkinson's disease. In all cohorts, we genotyped ATXN1 and ATXN2 CAG repeats. In addition, in the FTD cohort, we determined the number of HIT CAG repeats. The frequency of HIT IAs was higher in patients with FTD (6.9%) versus controls (2.9%) and in the C9orf72 expansion noncarriers (7.2%) versus controls (2.9%), although the difference was nonsignificant after correction for multiple testing. Compared with controls, progressive nonfluent aphasia (PNFA) groups showed a significantly higher frequency of HTT IAs (13.6% vs. 2.9% controls). For the ATXN2 gene, we observed an increase in IA frequency in AD cases (AD 4.1% vs. controls 1.8%) and in the behavioral FTD group (4.8% vs. 1.8%). For the ATXN1 gene, we found a significant increase of IAs in patients with PNFA (18.6%) versus controls (6.7%). In conclusion, our work suggests that the HTT and ATXN1 IAS may contribute to PNFA pathogenesis and point to a link between ATXN2 IAS and AD. (C) 2019 Elsevier Inc. All rights reserved.

Background/aims Few longitudinal studies have explored the progression of cognitive and functional impairment of patients with primary progressive aphasia (PPA). The aims of the study were to describe the clinical, neuroimaging, and genetic features of a cohort of 68 PPA patients, and to outline the natural history of the disease. Materials and methods A sample of 23 patients with the logopenic variant, 26 with the nonfluent/agrammatic variant, and 19 with the semantic variant was retrospectively collected and followed-up for a maximum of 6 years. Clinical-neuropsychological assessment, fluorodeoxyglucose positron emission tomographic imaging, and genetic analyses were acquired at baseline. Disease progression was evaluated in terms of language impairment, global cognitive decline, and functional dependency. Results During follow-up, one third of subjects presented total language loss, and 20% severe functional dependency. Global cognitive decline after the first year (hazard ratio, 5.93; confidence interval, 1.63-21.56) and high schooling (hazard ratio, 0.07; confidence interval, 0.008-0.74) represented risk factors for functional impairment. The apolipoprotein E status was associated with the progression of cognitive decline. Positive family history for dementia was frequent and 3 genetic autosomal dominant mutations were identified. Conclusions There were no differences in the progression of PPA subtypes. Genetics plays an important role in disease onset and progression.

ATENCIÓ: la correcció està també al DDD, cal relacionar??? https://ddd.uab.cat/record/226203 Altres ajuts: The following studies and consortia have contributed to this manuscript. Amsterdam dementia Cohort (ADC): Research of the Alzheimer center Amsterdam is part of the neurodegeneration research program of Amsterdam Neuroscience. The Alzheimer Center Amsterdam is supported by Stichting Alzheimer Nederland and Stichting VUmc fonds. The clinical database structure was developed with funding from Stichting Dioraphte. Genotyping of the Dutch case-control samples was performed in the context of EADB (European Alzheimer DNA biobank) funded by the JPco-fuND FP-829-029 (ZonMW projectnumber 733051061). 100-Plus study: We are grateful for the collaborative efforts of all participating centenarians and their family members and/or relations. This work was supported by Stichting Alzheimer Nederland (WE09.2014-03), Stichting Diorapthe, horstingstuit foundation, Memorabel (ZonMW projectnumber 733050814) and Stichting VUmc Fonds. Genotyping of the 100-Plus Study was performed in the context of EADB (European Alzheimer DNA biobank) funded by the JPco-fuND FP-829-029 (ZonMW projectnumber 733051061). German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe): This study/publication is part of the German Research Network on Dementia (KND), the German Research Network on Degenerative Dementia (KNDD; German Study on Ageing, Cognition and Dementia in Primary Care Patients; AgeCoDe), and the Health Service Research Initiative (Study on Needs, health service use, costs and health-related quality of life in a large sample of oldest-old primary care patients (85+; AgeQualiDe)) and was funded by the German Federal Ministry of Education and Research (grants KND: 01GI0102, 01GI0420, 01GI0422, 01GI0423, 01GI0429, 01GI0431, 01GI0433, 01GI0434; grants KNDD: 01GI0710, 01GI0711, 01GI0712, 01GI0713, 01GI0714, 01GI0715, 01GI0716; grants Health Service Research Initiative: 01GY1322A, 01GY1322B, 01GY1322C, 01GY1322D, 01GY1322E, 01GY1322F, 01GY1322G). Alfredo Ramirez was partly supported by the ADAPTED consortium: Alzheimer's disease Apolipoprotein Pathology for Treatment Elucidation and Development, which has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 115975. Brain compendium: This work was funded by the UK Medical Research Council (13044). P.F.C. is a Wellcome Trust principal Fellow (212219/Z/18/Z) and a UK NIHR Senior Investigator, who receives support from the Medical Research Council Mitochondrial Biology Unit (MC_UU_00015/9), and the National Institute for Health Research (NIHR) Biomedical Research Centre based at Cambridge University Hospitals NHS Foundation Trust and the University of Cambridge. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, or the Department of Health.Clinical AD, Sweden: We would like to thank UCL Genomics for performing the genotyping analyses. Danish data: The studies behind the Danish long-lived cases received funding from The National Program for Research Infrastructure 2007 (grant no. 09-063256), the Danish Agency for Science Technology and Innovation, the Velux Foundation, the US National Institute of Health (P01 AG08761), the Danish Agency for Science, Technology and Innovation/The Danish Council for Independent Research (grant no. 11-107308), the European Union's Seventh Framework Programme (FP7/2007-2011) under grant agreement no. 259679, the INTERREG 4 A programme Syddanmark-Schleswig-K.E.R.N. (by EU funds from the European Regional Development Fund), the CERA Foundation (Lyon), the AXA Research Fund, Paris, and The Health Foundation (Helsefonden), Copenhagen, Denmark. The GOYA study was conducted as part of the activities of the Danish Obesity Research Centre (DanORC, www.danorc.dk) and The MRC centre for Causal Analyses in Translational Epidemiology (MRC CAiTE). The genotyping for GOYA was funded by the Wellcome Trust (WT 084762). GOYA is a nested study within The Danish National Birth Cohort which was established with major funding from the Danish National Research Foundation. Additional support for this cohort has been obtained from the Pharmacy Foundation, the Egmont Foundation, The March of Dimes Birth Defects Foundation, the Augustinus Foundation, and the Health Foundation. Fundació ACE (FACE): We would like to thank patients and controls who participated in this project. We are indebted to Trinitat Port-Carbó and her family for their support of Fundació ACE research programs. Fundació ACE collaborates with the Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED, Spain) and is one of the participating centers of the Dementia Genetics Spanish Consortium (DEGESCO). Agustín Ruiz has received support from the EU/EFPIA Innovative Medicines Initiative Joint Undertaking ADAPTED Grant No. 115975 and by grants PI13/02434 and PI16/01861. Acción Estratégica en Salud, integrated in the Spanish National R + D + I Plan and financed by ISCIII (Instituto de Salud Carlos III)-Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (FEDER- "Una manera de Hacer Europa"), by Fundación bancaria "La Caixa" and Grifols SA (GR@ACE project). Genetics of Healthy Ageing Study (GEHA - NL): The work described in this paper was funded mainly by the EU GEHA Project contract no. LSHM-CT-2004-503-270. Gothenburg Birth Cohort (GBC) Studies: We would like to thank UCL Genomics for performing the genotyping analyses. The studies were supported by The Stena Foundation, The Swedish Research Council (2015-02830, 2013-8717), The Swedish Research Council for Health, Working Life and Wellfare (2013-1202, 2005-0762, 2008-1210, 2013-2300, 2013-2496, 2013-0475), The Brain Foundation, Sahlgrenska University Hospital (ALF), The Alzheimer's Association (IIRG-03-6168), The Alzheimer's Association Zenith Award (ZEN-01-3151), Eivind och Elsa K:son Sylvans Stiftelse, The Swedish Alzheimer Foundation. International FTD-Genomics Consortium (IFGC): International FTD-Genomics Consortium (IFGC): The authors thank the IFGC for providing relevant data to support the analyses presented in this manuscript. Further acknowledgments for IFGC (https://ifgcsite.wordpress.com/), e.g. full members list and affiliations, are found in the online supplementary files. IPDGC (​The International Parkinson Disease Genomics Consortium): We also would like to thank all members of the International Parkinson Disease Genomics Consortium (IPDGC). See for a complete overview of members, acknowledgements and funding http://pdgenetics.org/partners. Kompetenznetz Multiple Sklerose (KKNMS): This work was supported by the German Ministry for Education and Research (BMBF) as part of the "German Competence Network Multiple Sclerosis" (KKNMS) (grant nos. 01GI0916 and 01GI0917) and the Munich Cluster for Systems Neurology (SyNergy). TA was supported by the BMBF through the Integrated Network IntegraMent, under the auspices of the e:Med Programme (01ZX1614J). BH was supported by the EU Horizon 2020 project MultipleMS.Longitudinal Aging Study Amsterdam (LASA) is largely supported by a grant from the Netherlands Ministry of Health, Welfare and Sports, Directorate of Long-Term Care. The authors are grateful to all LASA participants, the fieldwork team and all researchers for their ongoing commitment to the study. Leiden Longevity Study: This study was supported by a grant from the Innovation-Oriented Research Program on Genomics (SenterNovem IGE05007), the Centre for Medical Systems Biology, and the Netherlands Consortium for Healthy Ageing (Grant 050-060-810), all in the framework of the Netherlands Genomics Initiative/Netherlands Organization for Scientific Research (NWO) and by Unilever Colworth.Maria Carolina Dalmasso: Georg Forster Research Award (Alexander von Humboldt Foundation). Mayo Clinic AD, DLB, PD, PSP: We thank the patients and their families for their participation, without whom these studies would not have been possible. Funding for this work was supported by National Institute on Aging [RF AG051504 to NET.; U01 AG046139 to NET]; and National Institute of Neurological Disorders and Stroke [R01 NS080820 to NET; P50 NS072187]. The Mayo Clinic is a Lewy Body Dementia Association (LBDA) Research Center of Excellence, American Parkinson Disease Association (APDA) Information and Referral Center and Center for Advanced Research, NINDS Tau Center without Walls (U54-NS100693) and is supported by Mayo Clinic AD and related dementias genetics program, The Little Family Foundation, the Mangurian Foundation for Lewy body research and NINDS R01 NS078086 (to OAR). The PD program at the Mayo Clinic Florida is also supported by the Mayo Clinic Center for Regenerative Medicine, Mayo Clinic Center for Individualized Medicine, Mayo Clinic Neuroscience Focused Research Team (Cecilia and Dan Carmichael Family Foundation, and the James C. and Sarah K. Kennedy Fund for Neurodegenerative Disease Research at Mayo Clinic in Florida), the gift from Carl Edward Bolch, Jr., and Susan Bass Bolch, and The Sol Goldman Charitable Trust. Samples included in this study are from the brain bank at Mayo Clinic in Jacksonville which is supported by CurePSP The online version of this article (10.1007/s00401-019-02026-8) contains supplementary material, which is available to authorized users.

Mutations in the microtubule-associated protein tau (MAPT) gene cause autosomal dominant frontotemporal lobar degeneration with tau inclusions (FTLD-tau). MAPT p.R406W carriers present clinically with progressive memory loss and neuropathologically with neuronal and glial tauopathy. However, the pathogenic events triggered by the expression of the mutant tau protein remain poorly understood. To identify the genes and pathways that are dysregulated in FTLD-tau, we performed transcriptomic analyses in induced pluripotent stem cell (iPSC)–derived neurons carrying MAPT p.R406W and CRISPR/Cas9-corrected isogenic controls. We found that the expression of the MAPT p.R406W mutation was sufficient to create a significantly different transcriptomic profile compared with that of the isogeneic controls and to cause the differential expression of 328 genes. Sixty-one of these genes were also differentially expressed in the same direction between MAPT p.R406W carriers and pathology-free human control brains. We found that genes differentially expressed in the stem cell models and human brains were enriched for pathways involving gamma-aminobutyric acid (GABA) receptors and pre-synaptic function. The expression of GABA receptor genes, including GABRB2 and GABRG2, were consistently reduced in iPSC-derived neurons and brains from MAPT p.R406W carriers. Interestingly, we found that GABA receptor genes, including GABRB2 and GABRG2, are significantly lower in symptomatic mouse models of tauopathy, as well as in brains with progressive supranuclear palsy. Genome wide association analyses reveal that common variants within GABRB2 are associated with increased risk for frontotemporal dementia (P −3). Thus, our systems biology approach, which leverages molecular data from stem cells, animal models, and human brain tissue can reveal novel disease mechanisms. Here, we demonstrate that MAPT p.R406W is sufficient to induce changes in GABA-mediated signaling and synaptic function, which may contribute to the pathogenesis of FTLD-tau and other primary tauopathies.

We evaluated the genetic contribution of the T cell-restricted intracellular antigen-1 gene (TIA1) in a European cohort of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) patients. Exonic resequencing of TIA1 in 1120 patients (693 FTD, 341 ALS, 86 FTD-ALS) and 1039 controls identified in total 5 rare heterozygous missense variants, affecting the TIA1 low-complexity domain (LCD). Only 1 missense variant, p.Met290Thr, identified in a familial FTD patient with disease onset at 64 years, was absent from controls yet received a combined annotation-dependent depletion score of 11.42. By contrast, 3 of the 4 variants also detected in unaffected controls, p.Val294Glu, p.Gln318Arg, and p.Ala381Thr, had combined annotation-dependent depletion scores greater than 20. Our findings in a large European patient-control series indicate that variants in TIA1 are not a common cause of ALS and FTD. The observation of recurring TIA1 missense variants in unaffected individuals lead us to conclude that the exact genetic contribution of TIA1 to ALS and FTD pathogenesis remains to be further elucidated. ispartof: NEUROBIOLOGY OF AGING vol:69 ispartof: location:United States status: published

Background During the twentieth century, frontotemporal dementia (FTD) was often misdiagnosed, confused with Alzheimer's disease or psychiatric disorders, jeopardizing care and research. Objective To analyze the FTD genes in the DNA samples of patients belonging to families clinically classified as probable Alzheimer's disease (FAD) in the early 1990s and not carrying mutation in the three main genes linked to FAD (Presenilin 1, Presenilin 2, and Amyloid precursor protein). Methods The genetic screening was performed on 63 probands diagnosed as FAD before the early 2000s. Results Four patients out of the 63 studied (4/63, 6.3%) resulted as carrying four different GRN genetic variations: p.T272SfsX10, p.R110X, p.C149LfsX10, and p.W304C. The first two mutations (p.T272SfsX10, p.R110X) are the most frequent ones in Italy in FTD patients; the latter two (p.C149LfsX10 and p.W304C) are not described in the scientific literature. Conclusion Our data suggest that it can be important to re-examine FAD patients diagnosed when the FTD spectrum was not well recognized and the causative FTD genes had not yet been identified. Moreover, we propose initially analyzing genes associated with the first form of suspected dementia and, if the results are negative, studying genes implicated in the other form of dementia.

Alzheimer's disease (AD) is a neurodegenerative disease affecting over 20 million people worldwide, mainly adult subjects in advanced age. Over 240 different fully penetrant autosomal dominant mutations in 532 families around the world have been described in three genes [i.e., amyloid precursor protein (APP), and presenilins (PSEN1 and PSEN2)] causing 50% of all Familial AD. We report a new mutation (p.Ile408Thr, c. 1223T>C) in the PSEN1 gene in one autosomal dominant Late Onset AD patient. The genetic variation occurred in a conserved domain of the protein and was present in the proband and in the younger sister who is likely to be prodromal AD. Thus, we suggest that this variant will have probably a pathogenic effect, hypothesizing a possible key role of this new mutation in the pathogenesis of Alzheimer's disease for this family.

Childhood overweight and the SNP rs41423247 of the glucocorticoid receptor gene (GR) were reported to represent predisposing factors for Eating Disorders (EDs). The distribution of the polymorphism was evaluated in 202 EDs patients, and in 116 healthy subjects. The Structured Clinical Interview for the DSM-IV and self-reported questionnaires were administered at the admission to the clinic and at 3 time points (end of a cognitive behavioral therapy, 3 and 6 years follow up). G-allele was associated with childhood overweight, depressive disorder comorbidity, and diagnostic instability. G-allele carriers reporting childhood overweight showed greater frequency of subjective binge eating and emotional eating.

Background: Loss-of-function mutations in GRN cause frontotemporal lobar degeneration (FTLD). Patients with GRN mutations present with a uniform subtype of TAR DNA-binding protein 43 (TDP-43) pathology at autopsy (FTLD-TDP type A); however, age at onset and clinical presentation are variable, even within families. We aimed to identify potential genetic modifiers of disease onset and disease risk in GRN mutation carriers. Methods: The study was done in three stages: a discovery stage, a replication stage, and a meta-analysis of the discovery and replication data. In the discovery stage, genome-wide logistic and linear regression analyses were done to test the association of genetic variants with disease risk (case or control status) and age at onset in patients with a GRN mutation and controls free of neurodegenerative disorders. Suggestive loci (p−5) were genotyped in a replication cohort of patients and controls, followed by a meta-analysis. The effect of genome-wide significant variants at the GFRA2 locus on expression of GFRA2 was assessed using mRNA expression studies in cerebellar tissue samples from the Mayo Clinic brain bank. The effect of the GFRA2 locus on progranulin concentrations was studied using previously generated ELISA-based expression data. Co-immunoprecipitation experiments in HEK293T cells were done to test for a direct interaction between GFRA2 and progranulin. Findings: Individuals were enrolled in the current study between Sept 16, 2014, and Oct 5, 2017. After quality control measures, statistical analyses in the discovery stage included 382 unrelated symptomatic GRN mutation carriers and 1146 controls free of neurodegenerative disorders collected from 34 research centres located in the USA, Canada, Australia, and Europe. In the replication stage, 210 patients (67 symptomatic GRN mutation carriers and 143 patients with FTLD without GRN mutations pathologically confirmed as FTLD-TDP type A) and 1798 controls free of neurodegenerative diseases were recruited from 26 sites, 20 of which overlapped with the discovery stage. No genome-wide significant association with age at onset was identified in the discovery or replication stages, or in the meta-analysis. However, in the case-control analysis, we replicated the previously reported TMEM106B association (rs1990622 meta-analysis odds ratio [OR] 0·54, 95% CI 0·46–0·63; p=3·54 × 10−16), and identified a novel genome-wide significant locus at GFRA2 on chromosome 8p21.3 associated with disease risk (rs36196656 meta-analysis OR 1·49, 95% CI 1·30–1·71; p=1·58 × 10−8). Expression analyses showed that the risk-associated allele at rs36196656 decreased GFRA2 mRNA concentrations in cerebellar tissue (p=0·04). No effect of rs36196656 on plasma and CSF progranulin concentrations was detected by ELISA; however, co-immunoprecipitation experiments in HEK293T cells did suggest a direct binding of progranulin and GFRA2. Interpretation: TMEM106B-related and GFRA2-related pathways might be future targets for treatments for FTLD, but the biological interaction between progranulin and these potential disease modifiers requires further study. TMEM106B and GFRA2 might also provide opportunities to select and stratify patients for future clinical trials and, when more is known about their potential effects, to inform genetic counselling, especially for asymptomatic individuals. Funding: National Institute on Aging, National Institute of Neurological Disorders and Stroke, Canadian Institutes of Health Research, Italian Ministry of Health, UK National Institute for Health Research, National Health and Medical Research Council of Australia, and the French National Research Agency.

Background Alzheimer's disease (AD) patients present high variability in the rate of cognitive decline. Despite the wide knowledge on factors influencing dementia risk, little is known on what accounts for AD progression. Previous studies on this topic have mainly analyzed each factor separately without taking into account the interaction between genetic and non-genetic factors. Objective The aim of the present study is to evaluate the role of demographic, clinical, therapeutic, and genetic factors and their interaction on cognitive decline among newly diagnosed AD patients. Methods We retrospectively selected 160 AD patients diagnosed at the Neurology Unit of Careggi University Hospital of Florence. We evaluated the occurrence of rapid cognitive changes defined as the worsening of more than four points at the Mini-Mental State Examination after 2-year follow up period. Results Among the 160 AD patients, 50% presented rapid disease progression. Extrapyramidal signs at disease onset were predictors of worse outcome (OR 2.2), especially among Apolipoprotein E (APOE) ɛ4 allele carriers, while the presence of family history for dementia decreased the risk of rapid progression by about 50%. Higher educated ɛ4-carriers showed a slower AD progression. We identified the chronic use of aspirin as potential secondary preventative strategy for the non ɛ4-carriers. Conclusion At dementia onset, some clinical and demographic data can be predictors of future progression. The outcomes of the present study support the already hypothesized interaction between genetic and non-genetic factors during disease course and suggest genetic-based approaches.

A new risk gene associated with amyotrophic lateral sclerosis (ALS) has recently been identified: the Tank-binding kinase 1 (TBK1) gene. Up to now, 90 TBK1 variants have been described in ALS patients with or without frontotemporal dementia (FTD), thus making TBK1 the third or fourth most frequent genetic cause of ALS and FTD. A point mutation analysis in a cohort of 69 Italian ALS patients was performed in order to analyze the frequency of TBK1 mutations and the correlation with clinical phenotypes. The analysis identified the novel variant p.Tyr424Asp in a patient with a rapid progression of the disease. Our data supports the implication of TBK1 in ALS pathogenesis in Italy.

According to the literature, the APP Ala713Thr mutation is associated with Alzheimer's disease and cerebral amyloid angiopathy. We describe a case of dementia clinically compatible with frontotemporal dementia in an APP Ala713Thr mutation carrier in which both [18F]Florbetapir PET uptake and Aβ1-42 cerebrospinal fluid levels were normal. Further evidences are required to establish if this association is only incidental.

In frontotemporal dementia (FTD), age at disease onset (AAO) is unpredictable in both early and late-onset cases; AAO variability is found even in autosomal dominant FTD. The present study was aimed at identifying genetic modifiers modulating AAO in a large cohort of Italian FTD patients. We conducted an association analysis on 411 FTD patients, belonging to 7 Italian Centers, and for whom AAO was available. Population structure was evaluated by principal component analysis to infer continuous axes of genetic variation, and single linear regression models were applied. A genetic score (GS) was calculated on the basis of suggestive single nucleotide polymorphisms (SNPs) found by association analyses. GS showed genome-wide significant slope decrease by −3.86 (95%CI: −4.64 to −3.07, p < 2 × 10−16) per standard deviation of the GS for 6 SNPs mapping to genes involved in neuronal development and signaling, axonal myelinization, and glutamatergic/GABA neurotransmission. An increase of the GS was associated with a decrease of the AAO. Our data indicate that there is indeed a genetic component that underpins and modulates up to 14.5% of variability of AAO in Italian FTD. Future studies on genetic modifiers in FTD are warranted.

// Laura Gragnani 1, * , Elisa Fognani 1, * , Valli De Re 2 , Massimo Libra 3 , Adriana Garozzo 3 , Patrizio Caini 1 , Guia Cerretelli 1 , Andrea Giovannelli 1 , Serena Lorini 1 , Monica Monti 1 , Silvia Bagnoli 4 , Irene Piaceri 4 and Anna Linda Zignego 1 1 Center for Systemic Manifestations of Hepatitis Viruses (MaSVE), Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy 2 Centro di Riferimento oncologico, National Cancer Institute, Aviano, Italy 3 Department of Biomedical and Biotechnological Sciences, Section of Microbiology, University of Catania, Italy 4 Department of Neuroscience, Psychology, Drug Research and Children’s Health, University of Florence, Florence, Italy * These authors contributed equally to this work Correspondence to: Anna Linda Zignego, email: a.zignego@dmi.unifi.it Keywords: HCV, mixed cryoglobulinemia, NOTCH4, HLA-II, lymphoma Received: January 31, 2017 Accepted: March 29, 2017 Published: May 06, 2017 ABSTRACT Mixed cryoglobulinemia (MC), is a HCV-related, clinically benign, lymphoproliferative disorder (LPD) that may evolve into a non Hodgkin’s lymphoma (NHL). Significant associations were found between two single nucleotide polymorphisms near NOTCH4 (rs2071286) and the HLA class II (rs9461776) genes and HCV-related MC syndrome (MCS). We analyzed NOTCH4 rs2071286 and HLA-II rs9461776 in 3 HCV-related LPD groups (asymptomatic MC, MCS, NHL) with HCV infection without lymphoproliferative disorders. We found a positive relationship between NOTCH4 rs207186 T minor allele frequency (MAF) and patients with HCV-related LPDs at risk of NHL (Chi-square test for trend = 14.84 p = 0.0001), in accordance with an over-dominant model in the NHL group (CT vs CC + TT, OR=1.88, 95% CI 1.24–2.83, p = 0.0026). Regarding HLA II rs9461776, G MAF increased in patients with HCV-related LPDs at risk of NHL (Chi-square test for trend = 8.40 p = 0.0038), in accordance with a recessive genotypic model in the NHL group (G/G vs A/A + A/G, OR = 11.07, 95% CI 2.37–51.64, p = 0.0022). Both NOTCH4 rs2071286 and HLA-II rs9461776 were present on chromosome 6 and showed D’ and r values of linkage disequilibrium (LD) of about 0.5 values, thereby suggesting there is no extensive LD in the HCV+ population. This data shows that the previously demonstrated association between NOTCH4 rs2071286 and HLA-II rs9461776 polymorphisms and HCV-related MCS could be extended to overall patients with HCV-related LPDs. The significant relationship between rs2071286 and rs9461776 MAF and the increased risk for NHL, suggests their use as non-invasive markers to categorize patients at risk of lymphoma.