MicroRNA Profiling of the Inflammatory Response after Early and Late Asthmatic Reaction.

A high proportion of house dust mite (HDM)-allergic asthmatics suffer from both an early asthmatic reaction (EAR) and a late asthmatic reaction (LAR) which follows it. In these patients, allergic inflammation is more relevant. MiRNAs have been shown to play an important role in the regulation of asthma's pathology. The aim of this study was to analyze the miRNA profile in patients with mild asthma and an HDM allergy after bronchial allergen provocation (BAP). Seventeen patients with EAR/no LAR and 17 patients with EAR plus LAR, determined by a significant fall in FEV1 after BAP, were differentially analyzed. As expected, patients with EAR plus LAR showed a more pronounced allergic inflammation and FEV1 delta drop after 24 h. NGS-miRNA analysis identified the down-regulation of miR-15a-5p, miR-15b-5p, and miR-374a-5p after BAP with the highest significance in patients with EAR plus LAR, which were negatively correlated with eNO and the maximum decrease in FEV1. These miRNAs have shared targets like CCND1, VEGFA, and GSK3B, which are known to be involved in airway remodeling, basement membrane thickening, and Extracellular Matrix deposition. NGS-profiling identified miRNAs involved in the inflammatory response after BAP with HDM extract, which might be useful to predict a LAR.

Episignatures Stratifying Helsmoortel-Van Der Aa Syndrome Show Modest Correlation with Phenotype.

Helsmoortel-Van der Aa syndrome (HVDAS) is a neurodevelopmental condition associated with intellectual disability/developmental delay, autism spectrum disorder, and multiple medical comorbidities. HVDAS is caused by mutations in activity-dependent neuroprotective protein (ADNP). A recent study identified genome-wide DNA methylation changes in 22 individuals with HVDAS, adding to the group of neurodevelopmental disorders with an epigenetic signature. This methylation signature segregated those with HVDAS into two groups based on the location of the mutations. Here, we conducted an independent study on 24 individuals with HVDAS and replicated the existence of the two mutation-dependent episignatures. To probe whether the two distinct episignatures correlate with clinical outcomes, we used deep behavioral and neurobiological data from two prospective cohorts of individuals with a genetic diagnosis of HVDAS. We found limited phenotypic differences between the two HVDAS-affected groups and no evidence that individuals with more widespread methylation changes are more severely affected. Moreover, in spite of the methylation changes, we observed no profound alterations in the blood transcriptome of individuals with HVDAS. Our data warrant caution in harnessing methylation signatures in HVDAS as a tool for clinical stratification, at least with regard to behavioral phenotypes.

Association between Polyunsaturated Fatty Acid Profile and Bronchial Inflammation in Bronchiolitis Obliterans.

Introduction: Bronchiolitis obliterans (BO) is a chronic lung disease, which occurs after an insult to the lower airways, in particular after airway infections or after stem cell transplantation, and which results in persistent inflammation. N-3 and n-6 polyunsaturated fatty acids (PUFA) have been shown to influence the inflammatory processes in chronic inflammatory conditions. Since BO is maintained by persistent pulmonary inflammation, a disbalanced n-6/n-3 fatty acid profile could support the inflammatory process in patients with BO and therefore, could become an approach to new therapeutic options. Methods: Twenty-five patients with BO (age: 13; 7-39) and 26 healthy controls (age: 19; 7-31) participated in the study. Lung function (forced viral capacity (FVC), forced expiratory volume 1 (FEV1), residual volume (RV)), and lung clearance index (LCI) were measured. Induced sputum was analyzed for cytology and cytokine levels (IL-1ß, IL-6, IL-8, TNF-α) using cytometric bead array (CBA). The PUFA profile was determined in the serum and induced sputum by gas chromatography. Results: Patients presented with significantly lower FVC and FEV1 as well as higher RV and LCI measurements compared to the control group. Apart from a massive airway inflammation indicated by elevated numbers of total cells and neutrophils, the CBA analysis showed significantly increased levels of IL-1ß, IL-6, and IL-8. The analysis of PUFA in sputum and serum revealed a significant difference in the ratio between the n-6 PUFA arachidonic acid (AA) and the n-3 PUFA docosahexaenoic acid (DHA) (AA : DHA). Furthermore, the AA : DHA ratio significantly correlated with the inflammatory cytokines in induced sputum. Conclusion: Lung function in BO is significantly impaired and associated with uncontrolled neutrophil-dominated airway inflammation. Furthermore, the imbalance in the AA/DHA ratio in favor of n-6 PUFA demonstrates a pro-inflammatory microenvironment in the cell membrane, which correlates with the inflammatory cytokines in induced sputum and might be an option for an anti-inflammatory therapy in BO.

DNA methylation signatures of aggression and closely related constructs: A meta-analysis of epigenome-wide studies across the lifespan.

DNA methylation profiles of aggressive behavior may capture lifetime cumulative effects of genetic, stochastic, and environmental influences associated with aggression. Here, we report the first large meta-analysis of epigenome-wide association studies (EWAS) of aggressive behavior (N = 15,324 participants). In peripheral blood samples of 14,434 participants from 18 cohorts with mean ages ranging from 7 to 68 years, 13 methylation sites were significantly associated with aggression (alpha = 1.2 × 10-7; Bonferroni correction). In cord blood samples of 2425 children from five cohorts with aggression assessed at mean ages ranging from 4 to 7 years, 83% of these sites showed the same direction of association with childhood aggression (r = 0.74, p = 0.006) but no epigenome-wide significant sites were found. Top-sites (48 at a false discovery rate of 5% in the peripheral blood meta-analysis or in a combined meta-analysis of peripheral blood and cord blood) have been associated with chemical exposures, smoking, cognition, metabolic traits, and genetic variation (mQTLs). Three genes whose expression levels were associated with top-sites were previously linked to schizophrenia and general risk tolerance. At six CpGs, DNA methylation variation in blood mirrors variation in the brain. On average 44% (range = 3-82%) of the aggression-methylation association was explained by current and former smoking and BMI. These findings point at loci that are sensitive to chemical exposures with potential implications for neuronal functions. We hope these results to be a starting point for studies leading to applications as peripheral biomarkers and to reveal causal relationships with aggression and related traits.

Effects of Hypoxia on RNA Cargo in Extracellular Vesicles from Human Adipose-Derived Stromal/Stem Cells.

Mesenchymal stromal/stem cells and their derivates are the most promising cell source for cell therapies in regenerative medicine. The application of extracellular vesicles (EVs) as cell-free therapeuticals requires particles with a maximum regenerative capability to enhance tissue and organ regeneration. The cargo of mRNA and microRNA (miR) in EVs after hypoxic preconditioning has not been extensively investigated. Therefore, the aim of our study was the characterization of mRNA and the miR loading of EVs. We further investigated the effects of the isolated EVs on renal tubular epithelial cells in vitro. We found 3131 transcripts to be significantly regulated upon hypoxia. Only 15 of these were downregulated, but 3116 were up-regulated. In addition, we found 190 small RNAs, 169 of these were miRs and 21 were piwi-interacting RNAs (piR). However, only 18 of the small RNAs were significantly altered, seven were miRs and 11 were piRs. Interestingly, all seven miRs were down-regulated after hypoxic pretreatment, whereas all 11 piRs were up-regulated. Gene ontology term enrichment and miR-target enrichment analysis of the mRNAs and miR were also performed in order to study the biological background. Finally, the therapeutic effect of EVs on human renal tubular epithelial cells was shown by the increased expression of three anti-inflammatory molecules after incubation with EVs from hypoxic pretreatment. In summary, our study demonstrates the altered mRNA and miR load in EVs after hypoxic preconditioning, and their anti-inflammatory effect on epithelial cells.

ADHD-associated PARK2 copy number variants: A pilot study on gene expression and effects of supplementary deprivation in patient-derived cell lines.

Recent studies show an association of Parkin RBR E3 ubiquitin protein ligase (PARK2) copy number variations (CNVs) with attention deficit hyperactivity disorder (ADHD). The aim of our pilot study to investigate gene expression associated with PARK2 CNVs in human-derived cellular models. We investigated gene expression in fibroblasts, hiPSC and dopaminergic neurons (DNs) of ADHD PARK2 deletion and duplication carriers by qRT PCR compared with healthy and ADHD cell lines without PARK2 CNVs. The selected 10 genes of interest were associated with oxidative stress response (TP53, NQO1, and NFE2L2), ubiquitin pathway (UBE3A, UBB, UBC, and ATXN3) and with a function in mitochondrial quality control (PINK1, MFN2, and ATG5). Additionally, an exploratory RNA bulk sequencing analysis in DNs was conducted. Nutrient deprivation as a supplementary deprivation stress paradigm was used to enhance potential genotype effects. At baseline, in fibroblasts, hiPSC, and DNs, there was no significant difference in gene expression after correction for multiple testing. After nutrient deprivation in fibroblasts NAD(P)H-quinone-dehydrogenase 1 (NQO1) expression was significantly increased in PARK2 CNV carriers. In a multivariate analysis, ubiquitin C (UBC) was significantly upregulated in fibroblasts of PARK2 CNV carriers. RNA sequencing analysis of DNs showed the strongest significant differential regulation in Neurontin (NNAT) at baseline and after nutrient deprivation. Our preliminary results suggest differential gene expression in pathways associated with oxidative stress, ubiquitine-proteasome, immunity, inflammation, cell growth, and differentiation, excitation/inhibition modulation, and energy metabolism in PARK2 CNV carriers compared to wildtype healthy controls and ADHD patients.

Dual Molecular Effects of Dominant RORA Mutations Cause Two Variants of Syndromic Intellectual Disability with Either Autism or Cerebellar Ataxia.

RORα, the RAR-related orphan nuclear receptor alpha, is essential for cerebellar development. The spontaneous mutant mouse staggerer, with an ataxic gait caused by neurodegeneration of cerebellar Purkinje cells, was discovered two decades ago to result from homozygous intragenic Rora deletions. However, RORA mutations were hitherto undocumented in humans. Through a multi-centric collaboration, we identified three copy-number variant deletions (two de novo and one dominantly inherited in three generations), one de novo disrupting duplication, and nine de novo point mutations (three truncating, one canonical splice site, and five missense mutations) involving RORA in 16 individuals from 13 families with variable neurodevelopmental delay and intellectual disability (ID)-associated autistic features, cerebellar ataxia, and epilepsy. Consistent with the human and mouse data, disruption of the D. rerio ortholog, roraa, causes significant reduction in the size of the developing cerebellum. Systematic in vivo complementation studies showed that, whereas wild-type human RORA mRNA could complement the cerebellar pathology, missense variants had two distinct pathogenic mechanisms of either haploinsufficiency or a dominant toxic effect according to their localization in the ligand-binding or DNA-binding domains, respectively. This dichotomous direction of effect is likely relevant to the phenotype in humans: individuals with loss-of-function variants leading to haploinsufficiency show ID with autistic features, while individuals with de novo dominant toxic variants present with ID, ataxia, and cerebellar atrophy. Our combined genetic and functional data highlight the complex mutational landscape at the human RORA locus and suggest that dual mutational effects likely determine phenotypic outcome.

The MiR-320 Family Is Strongly Downregulated in Patients with COVID-19 Induced Severe Respiratory Failure.

A high incidence of thromboembolic events associated with high mortality has been reported in severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infections with respiratory failure. The present study characterized post-transcriptional gene regulation by global microRNA (miRNA) expression in relation to activated coagulation and inflammation in 21 critically ill SARS-CoV-2 patients. The cohort consisted of patients with moderate respiratory failure (n = 11) and severe respiratory failure (n = 10) at an acute stage (day 0-3) and in the later course of the disease (>7 days). All patients needed supplemental oxygen and severe patients were defined by the requirement of positive pressure ventilation (intubation). Levels of D-dimers, activated partial thromboplastin time (aPTT), C-reactive protein (CRP), and interleukin (IL)-6 were significantly higher in patients with severe compared with moderate respiratory failure. Concurrently, next generation sequencing (NGS) analysis demonstrated increased dysregulation of miRNA expression with progression of disease severity connected to extreme downregulation of miR-320a, miR-320b and miR-320c. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis revealed involvement in the Hippo signaling pathway, the transforming growth factor (TGF)-ß signaling pathway and in the regulation of adherens junctions. The expression of all miR-320 family members was significantly correlated with CRP, IL-6, and D-dimer levels. In conclusion, our analysis underlines the importance of thromboembolic processes in patients with respiratory failure and emphasizes miRNA-320s as potential biomarkers for severe progressive SARS-CoV-2 infection.

[Genetic risk factors and their influence on neural development in autism spectrum disorders]. / Genetische Risikofaktoren und ihre Auswirkungen auf die neurale Entwicklung bei Autismus-Spektrum-Störungen.

Genetic risk factors and their influence on neural development in autism spectrum disorders Abstract. Abstract. Autism spectrum disorders are etiologically based on genetic and specific gene x biologically relevant environmental risk factors. They are diagnosed based on behavioral characteristics, such as impaired social communication and stereotyped, repetitive behavior and sensory as well as special interests. The genetic background is heterogeneous, i. e., it comprises diverse genetic risk factors across the disorder and high interindividual differences of specific genetic risk factors. Nevertheless, risk factors converge regarding underlying biological mechanisms and shared pathways, which likely cause the autism-specific behavioral characteristics. The current selective literature review summarizes differential genetic risk factors and focuses particularly on mechanisms and pathways currently being discussed by international research. In conclusion, clinically relevant aspects and open translational research questions are presented.

Synaptic, transcriptional and chromatin genes disrupted in autism.

The genetic architecture of autism spectrum disorder involves the interplay of common and rare variants and their impact on hundreds of genes. Using exome sequencing, here we show that analysis of rare coding variation in 3,871 autism cases and 9,937 ancestry-matched or parental controls implicates 22 autosomal genes at a false discovery rate (FDR) < 0.05, plus a set of 107 autosomal genes strongly enriched for those likely to affect risk (FDR < 0.30). These 107 genes, which show unusual evolutionary constraint against mutations, incur de novo loss-of-function mutations in over 5% of autistic subjects. Many of the genes implicated encode proteins for synaptic formation, transcriptional regulation and chromatin-remodelling pathways. These include voltage-gated ion channels regulating the propagation of action potentials, pacemaking and excitability-transcription coupling, as well as histone-modifying enzymes and chromatin remodellers-most prominently those that mediate post-translational lysine methylation/demethylation modifications of histones.

Impact of autism-associated genetic variants in interaction with environmental factors on ADHD comorbidities: an exploratory pilot study.

Attention-deficit/hyperactivity disorder (ADHD) is determined by genetic and environmental factors, and shares genetic risk with ASD. Functional single-nucleotide polymorphisms of the metabotropic glutamatergic signaling pathway are reported to increase the risk for ASD. The aim of this pilot study was to explore the main effects of respective ASD variants as well as their interaction effects with well-replicated ADHD environmental risk factors on the risk for ADHD, ADHD symptom severities, and comorbidities. We included 318 children with ADHD, aged 5-13 years, and their parents (N = 164 trios, N = 113 duos, N = 41 singletons). Interaction of ASD risk variants CYFIP1-rs7170637, CYFIP1-rs3693, CAMK4-rs25925, and GRM1-rs6923492 with prenatal biological and lifetime psychosocial risk factors was explored in a subsample with complete environmental risk factors (N = 139 trios, N = 83 duos, two singletons) by transmission disequilibrium test and stepwise regression analyses. We identified nominally significant (alpha < 0.05) GxE interactions of acute life events with CYFIP1-rs3693 on ADHD diagnosis (p = 0.004; fdr = 0.096) but no significant association of any single marker. Further results suggest that the risk for comorbid disruptive disorders was significantly modulated by GxE interactions between familial risk factors and CAMK4-rs25925 (p = 0.001; fdr = 0.018) and prenatal alcohol exposure with CYFIP1-rs3693 (p = 0.003; fdr = 0.027); both findings survived correction for multiple testing (fdr value < 0.05). Nominal significant GxE interactions moderating the risk for anxiety disorders have also been identified, but did not pass multiple testing corrections. This pilot study suggests that common ASD variants of the glutamatergic system interact with prenatal and lifetime psychosocial risk factors influencing the risk for ADHD common comorbidities and thus warrants replication in larger samples.

Ataxia telangiectasia alters the ApoB and reelin pathway.

Autosomal recessive ataxia telangiectasia (A-T) is characterized by radiosensitivity, immunodeficiency, and cerebellar neurodegeneration. A-T is caused by inactivating mutations in the ataxia telangiectasiamutated (ATM) gene, a serine-threonine protein kinase involved in DNA damage response and excitatory neurotransmission. The selective vulnerability of cerebellar Purkinje neurons (PN) to A-T is not well understood. Employing global proteomic profiling of cerebrospinal fluid from patients at ages around 15 years, we detected reduced calbindin, reelin, cerebellin-1, cerebellin-3, protocadherin fat 2, sempahorin 7A, and increased apolipoprotein B and J peptides. Bioinformatic enrichment was observed for pathways of lipoproteins, endocytosis, extracellular matrix receptor interaction, peptidase activity, adhesion, calcium binding, and complement immunity. This seemed important since secretion of reelin from glutamatergic afferent axons is crucial for PN lipoprotein receptor endocytosis and lipid signaling. Reelin expression is downregulated by irradiation and reelin/ApoB mutations are known causes of ataxia. Validation efforts in 2-month-old Atm-/- mice before onset of motor deficits confirmed cerebellar transcript reductions for reelin receptors Apoer2/Vldlr with increases for their ligands Apoe/Apoh and cholesterol 24-hydroxylase Cyp46a1. Concomitant dysregulations were found for Vglut2/Sema7a as climbing fiber markers, glutamate receptors like Grin2b, and calcium homeostasis factors (Atp2b2, Calb1, Itpr1), while factors involved in DNA damage, oxidative stress, neuroinflammation, and cell adhesion were normal at this stage. Quantitative immunoblots confirmed ApoB and ApoJ increases and VLDLR reduction in cerebellar tissue at the age of 2 months. These findings show that ApoB excess and reelin signaling deficits reflect the neurodegeneration in A-T in a sensitive and specific way. As extracellular factors, apolipoproteins and their cargo such as vitamin E may be useful for neuroprotective interventions.

Common functional variants of the glutamatergic system in Autism spectrum disorder with high and low intellectual abilities.

The genetic architecture underlying Autism spectrum disorder (ASD) has been suggested to differ between individuals with lower (IQ ≤ 70; LIQ) and higher intellectual abilities (IQ > 70; HIQ). Among the identified pathomechanisms, the glutamatergic signalling pathway is of specific interest in ASD. We investigated 187 common functional variants of this neurotransmitter system for association with ASD and with symptom severity in two independent samples, a German (German-ALL: N = 583 families) and the Autism Genome Project cohort (AGP-ALL: N = 2001 families), split into HIQ, and LIQ subgroups. We did not identify any association withstanding correction for multiple testing. However, we report a replicated nominal significant under-transmission (OR < 0.79, p < 0.04) of the AKAP13 rs745191-T allele in both LIQ cohorts, but not in the much larger HIQ cohorts. At the phenotypic level, we nominally replicated associations of CAMK2A-rs2241694 with non-verbal communication in both combined LIQ and HIQ ASD cohorts. Variants PLD1-rs2124147 and ADCY1-rs2461127 were nominally associated with impaired non-verbal abilities and AKAP2-rs3739456 with repetitive behaviour in both LIQ cohorts. All four LIQ-associated genes are involved in G-protein coupled signal transduction, a downstream pathway of metabotropic glutamate receptor activation. We conclude that functional common variants of glutamatergic genes do not have a strong impact on ASD, but seem to moderately affect ASD risk and phenotypic expression. Since most of our nominally replicated hits were identified in the LIQ cohort, further investigation of the glutamatergic system in this subpopulation might be warranted.

Conduct disorder in adolescent females: current state of research and study design of the FemNAT-CD consortium.

Conduct disorder (CD) is a common and highly impairing psychiatric disorder of childhood and adolescence that frequently leads to poor physical and mental health outcomes in adulthood. The prevalence of CD is substantially higher in males than females, and partly due to this, most research on this condition has used all-male or predominantly male samples. Although the number of females exhibiting CD has increased in recent decades, the majority of studies on neurobiological measures, neurocognitive phenotypes, and treatments for CD have focused on male subjects only, despite strong evidence for sex differences in the aetiology and neurobiology of CD. Here, we selectively review the existing literature on CD and related phenotypes in females, focusing in particular on sex differences in CD symptoms, patterns of psychiatric comorbidity, and callous-unemotional personality traits. We also consider studies investigating the neurobiology of CD in females, with a focus on studies using genetic, structural and functional neuroimaging, psychophysiological, and neuroendocrinological methods. We end the article by providing an overview of the study design of the FemNAT-CD consortium, an interdisciplinary, multi-level and multi-site study that explicitly focuses on CD in females, but which is also investigating sex differences in the causes, developmental course, and neurobiological correlates of CD.

Convergence of genes and cellular pathways dysregulated in autism spectrum disorders.

Rare copy-number variation (CNV) is an important source of risk for autism spectrum disorders (ASDs). We analyzed 2,446 ASD-affected families and confirmed an excess of genic deletions and duplications in affected versus control groups (1.41-fold, p = 1.0 × 10(-5)) and an increase in affected subjects carrying exonic pathogenic CNVs overlapping known loci associated with dominant or X-linked ASD and intellectual disability (odds ratio = 12.62, p = 2.7 × 10(-15), ∼3% of ASD subjects). Pathogenic CNVs, often showing variable expressivity, included rare de novo and inherited events at 36 loci, implicating ASD-associated genes (CHD2, HDAC4, and GDI1) previously linked to other neurodevelopmental disorders, as well as other genes such as SETD5, MIR137, and HDAC9. Consistent with hypothesized gender-specific modulators, females with ASD were more likely to have highly penetrant CNVs (p = 0.017) and were also overrepresented among subjects with fragile X syndrome protein targets (p = 0.02). Genes affected by de novo CNVs and/or loss-of-function single-nucleotide variants converged on networks related to neuronal signaling and development, synapse function, and chromatin regulation.

Personalized translational epilepsy research - Novel approaches and future perspectives: Part II: Experimental and translational approaches.

Despite the availability of more than 15 new "antiepileptic drugs", the proportion of patients with pharmacoresistant epilepsy has remained constant at about 20-30%. Furthermore, no disease-modifying treatments shown to prevent the development of epilepsy following an initial precipitating brain injury or to reverse established epilepsy have been identified to date. This is likely in part due to the polyetiologic nature of epilepsy, which in turn requires personalized medicine approaches. Recent advances in imaging, pathology, genetics, and epigenetics have led to new pathophysiological concepts and the identification of monogenic causes of epilepsy. In the context of these advances, the First International Symposium on Personalized Translational Epilepsy Research (1st ISymPTER) was held in Frankfurt on September 8, 2016, to discuss novel approaches and future perspectives for personalized translational research. These included new developments and ideas in a range of experimental and clinical areas such as deep phenotyping, quantitative brain imaging, EEG/MEG-based analysis of network dysfunction, tissue-based translational studies, innate immunity mechanisms, microRNA as treatment targets, functional characterization of genetic variants in human cell models and rodent organotypic slice cultures, personalized treatment approaches for monogenic epilepsies, blood-brain barrier dysfunction, therapeutic focal tissue modification, computational modeling for target and biomarker identification, and cost analysis in (monogenic) disease and its treatment. This report on the meeting proceedings is aimed at stimulating much needed investments of time and resources in personalized translational epilepsy research. This Part II includes the experimental and translational approaches and a discussion of the future perspectives, while the diagnostic methods, EEG network analysis, biomarkers, and personalized treatment approaches were addressed in Part I [1].

Personalized translational epilepsy research - Novel approaches and future perspectives: Part I: Clinical and network analysis approaches.

Despite the availability of more than 15 new "antiepileptic drugs", the proportion of patients with pharmacoresistant epilepsy has remained constant at about 20-30%. Furthermore, no disease-modifying treatments shown to prevent the development of epilepsy following an initial precipitating brain injury or to reverse established epilepsy have been identified to date. This is likely in part due to the polyetiologic nature of epilepsy, which in turn requires personalized medicine approaches. Recent advances in imaging, pathology, genetics and epigenetics have led to new pathophysiological concepts and the identification of monogenic causes of epilepsy. In the context of these advances, the First International Symposium on Personalized Translational Epilepsy Research (1st ISymPTER) was held in Frankfurt on September 8, 2016, to discuss novel approaches and future perspectives for personalized translational research. These included new developments and ideas in a range of experimental and clinical areas such as deep phenotyping, quantitative brain imaging, EEG/MEG-based analysis of network dysfunction, tissue-based translational studies, innate immunity mechanisms, microRNA as treatment targets, functional characterization of genetic variants in human cell models and rodent organotypic slice cultures, personalized treatment approaches for monogenic epilepsies, blood-brain barrier dysfunction, therapeutic focal tissue modification, computational modeling for target and biomarker identification, and cost analysis in (monogenic) disease and its treatment. This report on the meeting proceedings is aimed at stimulating much needed investments of time and resources in personalized translational epilepsy research. Part I includes the clinical phenotyping and diagnostic methods, EEG network-analysis, biomarkers, and personalized treatment approaches. In Part II, experimental and translational approaches will be discussed (Bauer et al., 2017) [1].

The neurobiological basis of human aggression: A review on genetic and epigenetic mechanisms.

Aggression is an evolutionary conserved behavior present in most species including humans. Inadequate aggression can lead to long-term detrimental personal and societal effects. Here, we differentiate between proactive and reactive forms of aggression and review the genetic determinants of it. Heritability estimates of aggression in general vary between studies due to differing assessment instruments for aggressive behavior (AB) as well as age and gender of study participants. In addition, especially non-shared environmental factors shape AB. Current hypotheses suggest that environmental effects such as early life stress or chronic psychosocial risk factors (e.g., maltreatment) and variation in genes related to neuroendocrine, dopaminergic as well as serotonergic systems increase the risk to develop AB. In this review, we summarize the current knowledge of the genetics of human aggression based on twin studies, genetic association studies, animal models, and epigenetic analyses with the aim to differentiate between mechanisms associated with proactive or reactive aggression. We hypothesize that from a genetic perspective, the aminergic systems are likely to regulate both reactive and proactive aggression, whereas the endocrine pathways seem to be more involved in regulation of reactive aggression through modulation of impulsivity. Epigenetic studies on aggression have associated non-genetic risk factors with modifications of the stress response and the immune system. Finally, we point to the urgent need for further genome-wide analyses and the integration of genetic and epigenetic information to understand individual differences in reactive and proactive AB. © 2015 Wiley Periodicals, Inc.

Genetic and functional analyses of SHANK2 mutations suggest a multiple hit model of autism spectrum disorders.

Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism. We then sequenced SHANK2 in 455 patients with ASD and 431 controls and integrated these results with those reported by Berkel et al. 2010 (n = 396 patients and n = 659 controls). We observed a significant enrichment of variants affecting conserved amino acids in 29 of 851 (3.4%) patients and in 16 of 1,090 (1.5%) controls (P = 0.004, OR = 2.37, 95% CI = 1.23-4.70). In neuronal cell cultures, the variants identified in patients were associated with a reduced synaptic density at dendrites compared to the variants only detected in controls (P = 0.0013). Interestingly, the three patients with de novo SHANK2 deletions also carried inherited CNVs at 15q11-q13 previously associated with neuropsychiatric disorders. In two cases, the nicotinic receptor CHRNA7 was duplicated and in one case the synaptic translation repressor CYFIP1 was deleted. These results strengthen the role of synaptic gene dysfunction in ASD but also highlight the presence of putative modifier genes, which is in keeping with the "multiple hit model" for ASD. A better knowledge of these genetic interactions will be necessary to understand the complex inheritance pattern of ASD.

Common variants in genes of the postsynaptic FMRP signalling pathway are risk factors for autism spectrum disorders.

Autism spectrum disorders (ASD) are heterogeneous disorders with a high heritability and complex genetic architecture. Due to the central role of the fragile X mental retardation gene 1 protein (FMRP) pathway in ASD we investigated common functional variants of ASD risk genes regulating FMRP. We genotyped ten SNPs in two German patient sets (N = 192 and N = 254 families, respectively) and report association for rs7170637 (CYFIP1; set 1 and combined sets), rs6923492 (GRM1; combined sets), and rs25925 (CAMK4; combined sets). An additional risk score based on variants with an odds ratio (OR) >1.25 in set 1 and weighted by their respective log transmitted/untransmitted ratio revealed a significant effect (OR 1.30, 95 % CI 1.11-1.53; P = 0.0013) in the combined German sample. A subsequent meta-analysis including the two German samples, the "Strict/European" ASD subsample of the Autism Genome Project (1,466 families) and a French case/control (541/366) cohort showed again association of rs7170637-A (OR 0.85, 95 % CI 0.75-0.96; P = 0.007) and rs25925-G (OR 1.31, 95 % CI 1.04-1.64; P = 0.021) with ASD. Functional analyses revealed that these minor alleles predicted to alter splicing factor binding sites significantly increase levels of an alternative mRNA isoform of the respective gene while keeping the overall expression of the gene constant. These findings underpin the role of ASD candidate genes in postsynaptic FMRP regulation suggesting that an imbalance of specific isoforms of CYFIP1, an FMRP interaction partner, and CAMK4, a transcriptional regulator of the FMRP gene, modulates ASD risk. Both gene products are related to neuronal regulation of synaptic plasticity, a pathomechanism underlying ASD and may thus present future targets for pharmacological therapies in ASD.