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As in other subfields of psychology, developmental science faces a long-standing problem of limited diversity in research participants. This issue especially raises concerns when researchers make unwarranted broad claims about their results, such as using generic language that implies that a finding is unvarying and applies across participants and contexts. Variation in editorial practices may contribute to the extent to which generic language is used or how much information is provided about participant demographics. The present study expands on an existing corpus of articles published in developmental psychology journals and examines the extent to which generic language differed by journal and sample characteristics (such as racial/ethnic diversity or sample size). We observed widespread use of generic language: 73% of articles included at least one generic statement in article components that were coded (i.e. titles, highlights, and abstracts). However, differences across journals were observed: Articles published in "Developmental Science" and "JECP" (which require authors to include short research highlights) tended to have higher rates of generic language than articles published in "Child Development" and "Developmental Psychology" (which did not require highlights). Articles that fully reported sample race and ethnicity also included fewer generic statements to describe their results than articles with more incomplete reporting. We conclude by highlighting the importance of editorial policies in shaping scholarship, as well as challenges and opportunities for researchers to consider when reporting demographic information in a global field and clearly and accurately communicating the importance of research findings.

When infants begin to eat solid foods (recommended at around 6 months of age), parents have a huge variety of choices in terms of what foods to offer. The present studies examine parents’ judgments about foods for infants. Participants included parents recruited from Prolific (n = 99), who were shown descriptions of foods offered to infants (including familiar and unfamiliar foods at 6-, 9-, and 12-months) and a set of control foods eaten by adults. Participants rated each food based on how appropriate they thought it was for an infant and how much they personally wanted to eat the food. Parents rated foods as more appropriate for infants if they were familiar (vs. unfamiliar) and offered to younger infants (6- vs. 12-month-olds, or infant foods vs. adult foods), but demonstrated the opposite pattern when considering whether they wanted to eat each food. Participants’ own food pickiness was related to their judgments about what they would eat, but not whether foods were appropriate for infants. Parents’ judgments of individual foods were inversely related: The more appropriate they rated each food for an infant, the less they were interested in eating that food. These findings are discussed in terms of potential barriers to engaging in social modeling (i.e., parents demonstrating eating and liking the foods they offer to their infants).

The COVID-19 pandemic has disrupted many facets of developmental research, including research that measures children’s eating behavior. Here, children’s food intake is often measured by weighing foods that children are offered before and after in-person testing sessions. Many studies also examine children’s food ratings (the extent to which they like or dislike a food), assessed via picture categorization tasks or hedonic scales. This paper reviews existing research on different methods for characterizing children’s eating behavior (with a focus on food intake, preferences, and concepts) and presents a feasibility study that examined whether children’s eating behaviors at home (including their food intake and ratings) can be measured via live video-chat sessions. The feasibility analyses revealed that an observational feeding paradigm at home yielded a majority (more than 70%) of video-chat recordings that had a sufficient view of the child and adequate sound and picture quality required for observational coding for the majority of the session’s duration. Such positioning would enable behavioral coding of child food intake, parent food talk, and meal characteristics. Moreover, children were able to answer questions to stories and express their preferences via researcher screen-share methods (which can assess children’s self-reported food preferences and beliefs) with low rates of exclusion across studies. The article ends with a discussion on the opportunities and challenges of using online platforms to conduct studies on children’s eating behaviors in their home environments during the COVID-19 pandemic and beyond.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by upper and lower motor neuron signs. There are, however, cases where upper motor neurons (UMNs) are predominantly affected, leading to clinical presentations of UMN-dominant ALS or primary lateral sclerosis. Furthermore, cases exhibiting an UMN-predominant pattern of motor neuron disease (MND) presenting with corticobasal syndrome (CBS) have been sparsely reported. This study aims to clarify the clinicopathological features of patients with UMN-predominant MND. We reviewed 24 patients with UMN-predominant MND with TDP-43 pathology in the presence or absence of frontotemporal lobar degeneration. Additionally, we reviewed the medical records of patients with pathologically-confirmed corticobasal degeneration (CBD) who received a final clinical diagnosis of CBS (n = 10) and patients with pathologically-confirmed progressive supranuclear palsy (PSP) who received a final clinical diagnosis of PSP syndrome (n = 10). Of 24 UMN-predominant MND patients, 20 had a clinical diagnosis of an atypical parkinsonian disorder, including CBS (n = 11) and PSP syndrome (n = 8). Only two patients had antemortem diagnoses of motor neuron disease. UMN-predominant MND patients with CBS less frequently exhibited apraxia than those with CBD, and they were less likely to meet clinical criteria for possible or probable CBS. Similarly, UMN-predominant MND patients with PSP syndrome less often met clinical criteria for probable PSP than PSP patients with PSP syndrome. Our findings suggest that UMN-predominant MND can mimic atypical parkinsonism, and should be considered in the differential diagnosis of CBS and PSP syndrome, in particular when criteria are not met., (© 2024 The Author(s). Brain Pathology published by John Wiley & Sons Ltd on behalf of International Society of Neuropathology.)

Background: The gene C9orf72 harbors a non-coding hexanucleotide repeat expansion known to cause amyotrophic lateral sclerosis and frontotemporal dementia. While previous studies have estimated the length of this repeat expansion in multiple tissues, technological limitations have impeded researchers from exploring additional features, such as methylation levels., Methods: We aimed to characterize C9orf72 repeat expansions using a targeted, amplification-free long-read sequencing method. Our primary goal was to determine the presence and subsequent quantification of observed methylation in the C9orf72 repeat expansion. In addition, we measured the repeat length and purity of the expansion. To do this, we sequenced DNA extracted from blood for 27 individuals with an expanded C9orf72 repeat., Results: For these individuals, we obtained a total of 7,765 on-target reads, including 1,612 fully covering the expanded allele. Our in-depth analysis revealed that the expansion itself is methylated, with great variability in total methylation levels observed, as represented by the proportion of methylated CpGs (13 to 66%). Interestingly, we demonstrated that the expanded allele is more highly methylated than the wild-type allele (P-Value = 2.76E-05) and that increased methylation levels are observed in longer repeat expansions (P-Value = 1.18E-04). Furthermore, methylation levels correlate with age at collection (P-Value = 3.25E-04) as well as age at disease onset (P-Value = 0.020). Additionally, we detected repeat lengths up to 4,088 repeats (~ 25 kb) and found that the expansion contains few interruptions in the blood., Conclusions: Taken together, our study demonstrates robust ability to quantify methylation of the expanded C9orf72 repeat, capturing differences between individuals harboring this expansion and revealing clinical associations., Competing Interests: Declarations. Ethics approval and consent to participate: All subjects agreed to be in the study, and biological specimens were obtained after informed consent with approval from the Mayo Clinic Institutional Review Board (IRB). Consent for publication: Not applicable. Competing interests: MDJ and RR hold a patent on methods to screen for the C9orf72 hexanucleotide repeat expansion., (© 2024. The Author(s).)

The most prominent genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) is a repeat expansion in the gene C9orf72. Importantly, the transcriptomic consequences of the C9orf72 repeat expansion remain largely unclear. Here, we used short-read RNA sequencing (RNAseq) to profile the cerebellar transcriptome, detecting alterations in patients with a C9orf72 repeat expansion. We focused on the cerebellum, since key C9orf72-related pathologies are abundant in this neuroanatomical region, yet TDP-43 pathology and neuronal loss are minimal. Consistent with previous work, we showed a reduction in the expression of the C9orf72 gene and an elevation in homeobox genes, when comparing patients with the expansion to both patients without the C9orf72 repeat expansion and control subjects. Interestingly, we identified more than 1000 alternative splicing events, including 4 in genes previously associated with ALS and/or FTLD. We also found an increase of cryptic splicing in C9orf72 patients compared to patients without the expansion and controls. Furthermore, we demonstrated that the expression level of select RNA-binding proteins is associated with cryptic splice junction inclusion. Overall, this study explores the presence of widespread transcriptomic changes in the cerebellum, a region not confounded by severe neurodegeneration, in post-mortem tissue from C9orf72 patients., (© 2024. The Author(s).)

Arginine-rich dipeptide repeat proteins (R-DPRs), abnormal translational products of a GGGGCC hexanucleotide repeat expansion in C9ORF72 , play a critical role in C9ORF72 -related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), the most common genetic form of the disorders (c9ALS/FTD). R-DPRs form liquid condensates in vitro, induce stress granule formation in cultured cells, aggregate, and sometimes coaggregate with TDP-43 in postmortem tissue from patients with c9ALS/FTD. However, how these processes are regulated is unclear. Here, we show that loss of poly(ADP-ribose) (PAR) suppresses neurodegeneration in c9ALS/FTD fly models and neurons differentiated from patient-derived induced pluripotent stem cells. Mechanistically, PAR induces R-DPR condensation and promotes R-DPR-induced stress granule formation and TDP-43 aggregation. Moreover, PAR associates with insoluble R-DPR and TDP-43 in postmortem tissue from patients. These findings identified PAR as a promoter of R-DPR toxicity and thus a potential target for treating c9ALS/FTD.

Frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP) is a complex heterogeneous neurodegenerative disorder for which mechanisms are poorly understood. To explore transcriptional changes underlying FTLD-TDP, we performed RNA-sequencing on 66 genetically unexplained FTLD-TDP patients, 24 FTLD-TDP patients with GRN mutations and 24 control participants. Using principal component analysis, hierarchical clustering, differential expression and coexpression network analyses, we showed that GRN mutation carriers and FTLD-TDP-A patients without a known mutation shared a common transcriptional signature that is independent of GRN loss-of-function. After combining both groups, differential expression as compared to the control group and coexpression analyses revealed alteration of processes related to immune response, synaptic transmission, RNA metabolism, angiogenesis and vesicle-mediated transport. Deconvolution of the data highlighted strong cellular alterations that were similar in FTLD-TDP-A and GRN mutation carriers with NSF as a potentially important player in both groups. We propose several potentially druggable pathways such as the GABAergic, GDNF and sphingolipid pathways. Our findings underline new disease mechanisms and strongly suggest that affected pathways in GRN mutation carriers extend beyond GRN and contribute to genetically unexplained forms of FTLD-TDP-A., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Guarantors of Brain.)

The current standard of practice for patients with acute ischemic stroke treated with intravenous tissue-type plasminogen activator (tPA) requires critical monitoring for 24-hours post-treatment due to the risk of symptomatic intracranial hemorrhage (sICH). This is a costly and resource intensive practice. In this study, we evaluated the safety and efficacy of this standard 24-hour ICU monitoring period compared with a shorter 12-hour ICU monitoring period for minor stroke patients (NIHSS 0-5) treated with tPA only. Stroke mimics and those who underwent thrombectomy were excluded. The primary outcome was length of hospital stay. Secondary outcome measures included sICH, deep venous thrombosis (DVT), pulmonary embolism (PE), pneumonia, favorable discharge to home or acute rehabilitation, readmission within 30 days, and favorable functional outcome defined as modified Rankin scale (mRS) of 0-2 at 90 days. Of the 122 patients identified, 77 were in the 24-hour protocol and 45 were in 12-hour protocol. There was significant difference in length of hospital stay for the 24-hour ICU protocol (2.8 days) compared with the 12-hour ICU protocol (1.8 days) ( P < 0.001). Although not statistically significant, the 12-hour group had favorable rates of sICH, 30-day readmission rates, favorable discharge disposition and favorable functional outcome. Rates of DVT, PE and aspiration pneumonia were identical between the groups. Compared with 24-hour ICU monitoring, 12-hour ICU monitoring after thrombolysis for minor acute ischemic stroke was not associated with any increase in adverse outcomes. A randomized trial is needed to verify these findings., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: We would like to disclose conflicts of interest including receiving consulting fees from Abbot, receiving compensation from Women Health Initiative, and receiving research funding from National Institute of Neurological Diseases and Stroke., (© The Author(s) 2022.)

Purpose: We hypothesize treatment with nivolumab and stereotactic radiosurgery (SRS) will be feasible and well tolerated, and may improve intracranial tumor control rates compared with SRS alone., Methods and Materials: The study was designed as a prospective, single-arm, nonrandomized, open-label, phase 1b trial of nivolumab and SRS among patients with metastatic breast cancer brain metastases. Key eligibility criteria included patients with breast cancer brain metastases of all subtypes, age ≥18, Eastern Cooperative Oncology Group Performance Status ≤2 with ≤10 brain metastases. Treatment was initiated with a dose of nivolumab (480 mg intravenously) that was repeated every 4 weeks. The initial dose of nivolumab was followed 1 week later by SRS. This study is closed to accrual and is registered with ClinicalTrials.gov, NCT03807765., Results: Between February 2019 and July 2020, a total of 12 patients were treated to 17 lesions. No dose limiting toxicities were noted in our patient population. The most common neurologic adverse events included grade 1 to 2 headaches and dizziness occurring in 5 (42%) of patients. Median intracranial control was 6.2 months (95% confidence interval, 3-14 months) with 6- and 12-month control rates of 55% and 22%, respectively. A total of 4 patients had systemic progression during the study. Median time to systemic progression free survival has not been reached with 6- and-12 month rates of 63% and 51%, respectively., Conclusions: Nivolumab and SRS is a safe and feasible treatment option in breast cancer brain metastases. Preliminary data reveals activity in certain breast cancer patients to study therapy., (© 2021 The Author(s).)

To examine the length of a hexanucleotide expansion in C9orf72, which represents the most frequent genetic cause of frontotemporal lobar degeneration and motor neuron disease, we employed a targeted amplification-free long-read sequencing technology: No-Amp sequencing. In our cross-sectional study, we assessed cerebellar tissue from 28 well-characterized C9orf72 expansion carriers. We obtained 3507 on-target circular consensus sequencing reads, of which 814 bridged the C9orf72 repeat expansion (23%). Importantly, we observed a significant correlation between expansion sizes obtained using No-Amp sequencing and Southern blotting (P = 5.0 × 10-4). Interestingly, we also detected a significant survival advantage for individuals with smaller expansions (P = 0.004). Additionally, we uncovered that smaller expansions were significantly associated with higher levels of C9orf72 transcripts containing intron 1b (P = 0.003), poly(GP) proteins (P = 1.3 × 10- 5), and poly(GA) proteins (P = 0.005). Thorough examination of the composition of the expansion revealed that its GC content was extremely high (median: 100%) and that it was mainly composed of GGGGCC repeats (median: 96%), suggesting that expanded C9orf72 repeats are quite pure. Taken together, our findings demonstrate that No-Amp sequencing is a powerful tool that enables the discovery of relevant clinicopathological associations, highlighting the important role played by the cerebellar size of the expanded repeat in C9orf72-linked diseases., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain.)

Cardiac sympathetic denervation (CSD) for refractory ventricular tachycardia (VT) has been shown to decrease VT recurrence and defibrillator shocks in patients with ischemic and nonischemic cardiomyopathy. Here and in the accompanying Video, we demonstrate the technique for minimally invasive CSD, highlight important technical points, and report surgical outcomes. CSD is accomplished through bilateral resection of the inferior one-third to one-half of the stellate ganglion en bloc with T2-T4 sympathectomy. Despite the high potential for perioperative risk, most patients do not have serious complications. We find that surgical CSD can be performed safely in an attempt to liberate patients from refractory VT., Competing Interests: Funding Support and Author Disclosures Dr. Lee discloses a financial relationship with AstraZeneca, Bristol Myers Squibb, and Genentech. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2021 The Society of Thoracic Surgeons and the American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Emerging adults differ in terms of the extent to which they perceive themselves as adults. We examined how the ability to perform activities related to independent living (i.e., instrumental activities of daily living [IADLs]) was associated with perceived adulthood. Data were collected from 236 emerging adults in college. Results suggested that IADL scores were positively related to perceived adulthood and achieved criteria of adulthood even after controlling for race, year in school, age, and sex. Results are discussed in terms of the development and importance of IADLs during emerging adulthood.

Active learning emphasizes student engagement and collaboration instead of more passive learning, which involves primarily listening to lectures in the classroom setting. The benefits of active learning are many with an emphasis on the expansion of higher-order processing and critical thinking skills. Active learning can be found in many best practice approaches in the Medicine, Science, Engineering, and Mathematics (MSTEM) fields. Hack-a-thon and hack events are examples of active learning. These are gaining popularity in research institutes, and specifically in engineering, computer science, business, and healthcare settings. Wikipedia defines hack-a-thon as the blending of the words "hack," referring to exploratory programming, and "marathon," referring to a timed event. This article describes a hack-a-thon approach for active learning in the classroom setting.

Background and Purpose: Recent trials have shown benefit of thrombectomy in patients selected by penumbral imaging in the late (>6 hours) window. However, the role penumbral imaging is not clear in the early (0-6 hours) window. We sought to evaluate if time to treatment modifies the effect of endovascular reperfusion in stroke patients with evidence of salvageable tissue on CT perfusion (CTP)., Methods: We retrospectively analyzed consecutive patients who underwent thrombectomy in a single center. Demographics, comorbidities, National Institute of Health Stroke Scale (NIHSS), rtPA administration, ASPECTS, core infarct volume, onset to skin puncture time, recanalization (mTICI IIb/III), final infarct volume were compared between patients with good and poor 90-day outcomes (mRS 0-2 vs. 3-6). Multivariable logistic regression analyses were used to identify independent predictors of a good (mRS 0-2) 90-day outcome., Results: A total of 235 patients were studied, out of which 52.3% were female. Univariate analysis showed that the groups (early vs. late) were balanced for age (P = .23), NIHSS (P = .63), vessel occlusion location (P = .78), initial core infarct volume (P = .15), and recanalization (mTICI IIb/III) rates (P = .22). Favorable outcome (mRS 0-2) at 90 days (P = .30) were similar. There was a significant difference in final infarct volume (P = .04). Shift analysis did not reveal any significant difference in 90-day outcome (P = .14). After adjustment; age (P < .001), NIHSS (P = .01), recanalization (P = .008), and final infarct volume (P < .001) were predictive of favorable outcome., Conclusions: Penumbral imaging-based selection of patients for thrombectomy is effective regardless of onset time and yields similar functional outcomes in early and late window patients., (© 2020 by the American Society of Neuroimaging.)

Background: A repeat expansion in the C9orf72-SMCR8 complex subunit (C9orf72) is the most common genetic cause of two debilitating neurodegenerative diseases: amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Currently, much remains unknown about which variables may modify these diseases. We sought to investigate associations between C9orf72 promoter methylation, RNA expression levels, and repeat length, their potential effects on disease features, as well as changes over time and within families., Methods: All samples were obtained through the ALS Center at Mayo Clinic Florida. Our primary cohort included 75 unrelated patients with an expanded C9orf72 repeat, 33 patients who did not possess this expansion, and 20 control subjects without neurodegenerative diseases. Additionally, 67 members from 17 independent C9orf72 families were selected of whom 33 harbored this expansion. Longitudinally collected samples were available for 35 C9orf72 expansion carriers. To increase our understanding of C9orf72-related diseases, we performed quantitative methylation-sensitive restriction enzyme-based assays, digital molecular barcoding, quantitative real-time PCR, and Southern blotting., Results: In our primary cohort, higher methylation levels were observed in patients with a C9orf72 repeat expansion than in patients without this expansion (p = 1.7e-13) or in control subjects (p = 3.3e-07). Moreover, we discovered that an increase in methylation levels was associated with a decrease in total C9orf72 transcript levels (p = 5.5e-05). These findings aligned with our observation that C9orf72 expansion carriers had lower expression levels of total C9orf72 transcripts than patients lacking this expansion (p = 3.7e-07) or control subjects (p = 9.1e-05). We also detected an elevation of transcripts containing intron 1a (upstream of the repeat) in patients carrying a C9orf72 repeat expansion compared to (disease) controls (p ≤ 0.01), an indication of abortive transcripts and/or a switch in transcription start site usage. While methylation and expression levels were relatively stable over time, fluctuations were seen in repeat length. Interestingly, contractions occurred frequently in parent-offspring transmissions (> 50%), especially in paternal transmissions. Furthermore, smaller repeat lengths were detected in currently unaffected individuals than in affected individuals (p = 8.9e-04) and they were associated with an earlier age at collection (p = 0.008)., Conclusions: In blood from C9orf72 expansion carriers, we found elevated methylation levels, reduced expression levels, and unstable expansions that tend to contract in successive generations, arguing against anticipation.

The majority of the clinico-pathological variability observed in patients harboring a repeat expansion in the C9orf72-SMCR8 complex subunit (C9orf72) remains unexplained. This expansion, which represents the most common genetic cause of frontotemporal lobar degeneration (FTLD) and motor neuron disease (MND), results in a loss of C9orf72 expression and the generation of RNA foci and dipeptide repeat (DPR) proteins. The C9orf72 protein itself plays a role in vesicular transport, serving as a guanine nucleotide exchange factor that regulates GTPases. To further elucidate the mechanisms underlying C9orf72-related diseases and to identify potential disease modifiers, we performed an extensive RNA sequencing study. We included individuals for whom frontal cortex tissue was available: FTLD and FTLD/MND patients with (n = 34) or without (n = 44) an expanded C9orf72 repeat as well as control subjects (n = 24). In total, 6706 genes were differentially expressed between these groups (false discovery rate [FDR] < 0.05). The top gene was C9orf72 (FDR = 1.41E-14), which was roughly two-fold lower in C9orf72 expansion carriers than in (disease) controls. Co-expression analysis revealed groups of correlated genes (modules) that were enriched for processes such as protein folding, RNA splicing, synaptic signaling, metabolism, and Golgi vesicle transport. Within our cohort of C9orf72 expansion carriers, machine learning uncovered interesting candidates associated with clinico-pathological features, including age at onset (vascular endothelial growth factor A [VEGFA]), C9orf72 expansion size (cyclin dependent kinase like 1 [CDKL1]), DPR protein levels (eukaryotic elongation factor 2 kinase [EEF2K]), and survival after onset (small G protein signaling modulator 3 [SGSM3]). Given the fact that we detected a module involved in vesicular transport in addition to a GTPase activator (SGSM3) as a potential modifier, our findings seem to suggest that the presence of a C9orf72 repeat expansion might hamper vesicular transport and that genes affecting this process may modify the phenotype of C9orf72-linked diseases.

Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) represents the most common pathological subtype of FTLD. We established the international FTLD-TDP whole-genome sequencing consortium to thoroughly characterize the known genetic causes of FTLD-TDP and identify novel genetic risk factors. Through the study of 1131 unrelated Caucasian patients, we estimated that C9orf72 repeat expansions and GRN loss-of-function mutations account for 25.5% and 13.9% of FTLD-TDP patients, respectively. Mutations in TBK1 (1.5%) and other known FTLD genes (1.4%) were rare, and the disease in 57.7% of FTLD-TDP patients was unexplained by the known FTLD genes. To unravel the contribution of common genetic factors to the FTLD-TDP etiology in these patients, we conducted a two-stage association study comprising the analysis of whole-genome sequencing data from 517 FTLD-TDP patients and 838 controls, followed by targeted genotyping of the most associated genomic loci in 119 additional FTLD-TDP patients and 1653 controls. We identified three genome-wide significant FTLD-TDP risk loci: one new locus at chromosome 7q36 within the DPP6 gene led by rs118113626 (p value = 4.82e - 08, OR = 2.12), and two known loci: UNC13A, led by rs1297319 (p value = 1.27e - 08, OR = 1.50) and HLA-DQA2 led by rs17219281 (p value = 3.22e - 08, OR = 1.98). While HLA represents a locus previously implicated in clinical FTLD and related neurodegenerative disorders, the association signal in our study is independent from previously reported associations. Through inspection of our whole-genome sequence data for genes with an excess of rare loss-of-function variants in FTLD-TDP patients (n ≥ 3) as compared to controls (n = 0), we further discovered a possible role for genes functioning within the TBK1-related immune pathway (e.g., DHX58, TRIM21, IRF7) in the genetic etiology of FTLD-TDP. Together, our study based on the largest cohort of unrelated FTLD-TDP patients assembled to date provides a comprehensive view of the genetic landscape of FTLD-TDP, nominates novel FTLD-TDP risk loci, and strongly implicates the immune pathway in FTLD-TDP pathogenesis.

Background: Many neurodegenerative diseases are caused by nucleotide repeat expansions, but most expansions, like the C9orf72 'GGGGCC' (G 4 C 2 ) repeat that causes approximately 5-7% of all amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) cases, are too long to sequence using short-read sequencing technologies. It is unclear whether long-read sequencing technologies can traverse these long, challenging repeat expansions. Here, we demonstrate that two long-read sequencing technologies, Pacific Biosciences' (PacBio) and Oxford Nanopore Technologies' (ONT), can sequence through disease-causing repeats cloned into plasmids, including the FTD/ALS-causing G 4 C 2 repeat expansion. We also report the first long-read sequencing data characterizing the C9orf72 G 4 C 2 repeat expansion at the nucleotide level in two symptomatic expansion carriers using PacBio whole-genome sequencing and a no-amplification (No-Amp) targeted approach based on CRISPR/Cas9., Results: Both the PacBio and ONT platforms successfully sequenced through the repeat expansions in plasmids. Throughput on the MinION was a challenge for whole-genome sequencing; we were unable to attain reads covering the human C9orf72 repeat expansion using 15 flow cells. We obtained 8× coverage across the C9orf72 locus using the PacBio Sequel, accurately reporting the unexpanded allele at eight repeats, and reading through the entire expansion with 1324 repeats (7941 nucleotides). Using the No-Amp targeted approach, we attained > 800× coverage and were able to identify the unexpanded allele, closely estimate expansion size, and assess nucleotide content in a single experiment. We estimate the individual's repeat region was > 99% G 4 C 2 content, though we cannot rule out small interruptions., Conclusions: Our findings indicate that long-read sequencing is well suited to characterizing known repeat expansions, and for discovering new disease-causing, disease-modifying, or risk-modifying repeat expansions that have gone undetected with conventional short-read sequencing. The PacBio No-Amp targeted approach may have future potential in clinical and genetic counseling environments. Larger and deeper long-read sequencing studies in C9orf72 expansion carriers will be important to determine heterogeneity and whether the repeats are interrupted by non-G 4 C 2 content, potentially mitigating or modifying disease course or age of onset, as interruptions are known to do in other repeat-expansion disorders. These results have broad implications across all diseases where the genetic etiology remains unclear.

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<1 × 10 -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., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Loss-of-function mutations in progranulin (GRN) and a non-coding (GGGGCC) n hexanucleotide repeat expansions in C9ORF72 are the two most common genetic causes of frontotemporal lobar degeneration with aggregates of TAR DNA binding protein 43 (FTLD-TDP). TMEM106B encodes a type II transmembrane protein with unknown function. Genetic variants in TMEM106B associated with reduced TMEM106B levels have been identified as disease modifiers in individuals with GRN mutations and C9ORF72 expansions. Recently, loss of Tmem106b has been reported to protect the FTLD-like phenotypes in Grn-/- mice. Here, we generated Tmem106b-/- mice and examined whether loss of Tmem106b could rescue FTLD-like phenotypes in an AAV mouse model of C9ORF72-repeat induced toxicity. Our results showed that neither partial nor complete loss of Tmem106b was able to rescue behavioral deficits induced by the expression of (GGGGCC) 66 repeats (66R). Loss of Tmem106b also failed to ameliorate 66R-induced RNA foci, dipeptide repeat protein formation and pTDP-43 pathological burden. We further found that complete loss of Tmem106b increased astrogliosis, even in the absence of 66R, and failed to rescue 66R-induced neuronal cell loss, whereas partial loss of Tmem106b significantly rescued the neuronal cell loss but not neuroinflammation induced by 66R. Finally, we showed that overexpression of 66R did not alter expression of Tmem106b and other lysosomal genes in vivo, and subsequent analyses in vitro found that transiently knocking down C9ORF72, but not overexpression of 66R, significantly increased TMEM106B and other lysosomal proteins. In summary, reducing Tmem106b levels failed to rescue FTLD-like phenotypes in a mouse model mimicking the toxic gain-of-functions associated with overexpression of 66R. Combined with the observation that loss of C9ORF72 and not 66R overexpression was associated with increased levels of TMEM106B, this work suggests that the protective TMEM106B haplotype may exert its effect in expansion carriers by counteracting lysosomal dysfunction resulting from a loss of C9ORF72.