Search results for "Format"
showing 10 items of 24643 documents
Genome-wide association scan identifies new variants associated with a cognitive predictor of dyslexia
2019
Developmental dyslexia (DD) is one of the most prevalent learning disorders, with high impact on school and psychosocial development and high comorbidity with conditions like attention-deficit hyperactivity disorder (ADHD), depression, and anxiety. DD is characterized by deficits in different cognitive skills, including word reading, spelling, rapid naming, and phonology. To investigate the genetic basis of DD, we conducted a genome-wide association study (GWAS) of these skills within one of the largest studies available, including nine cohorts of reading-impaired and typically developing children of European ancestry (N = 2562–3468). We observed a genome-wide significant effect (p < 1 × 10…
Heterozygous deletion of the LRFN2 gene is associated with working memory deficits
2016
International audience; Learning disabilities (LDs) are a clinically and genetically heterogeneous group of diseases. Array-CGH and high-throughput sequencing have dramatically expanded the number of genes implicated in isolated intellectual disabilities and LDs, highlighting the implication of neuron-specific post-mitotic transcription factors and synaptic proteins as candidate genes. We report a unique family diagnosed with autosomal dominant learning disability and a 6p21 microdeletion segregating in three patients. The 870 kb microdeletion encompassed the brain-expressed gene LRFN2, which encodes for a synaptic cell adhesion molecule. Neuropsychological assessment identified selective w…
Meta-analysis identifies novel risk loci and yields systematic insights into the biology of male-pattern baldness
2017
Male-pattern baldness (MPB) is a common and highly heritable trait characterized by androgen-dependent, progressive hair loss from the scalp. Here, we carry out the largest GWAS meta-analysis of MPB to date, comprising 10,846 early-onset cases and 11,672 controls from eight independent cohorts. We identify 63 MPB-associated loci (P<5 × 10−8, METAL) of which 23 have not been reported previously. The 63 loci explain ∼39% of the phenotypic variance in MPB and highlight several plausible candidate genes (FGF5, IRF4, DKK2) and pathways (melatonin signalling, adipogenesis) that are likely to be implicated in the key-pathophysiological features of MPB and may represent promising targets for the de…
12q14.3 microdeletion involving HMGA2 gene cause a Silver-Russell syndrome-like phenotype: a case report and review of the literature
2020
Abstract Background Silver-Russell Syndrome (SRS) is a genetic disorder characterized by intrauterine and postnatal growth restriction and normal head circumference with consequent relative macrocephaly. Addictional findings are protruding forehead in early life, body asymmetry (of upper and lower limbs) and substantial feeding difficulties. Although several genetic mechanisms that cause the syndrome are known, more than 40% of patients with a SRS-like phenotype remain without an etiological diagnosis. In the last few years, different clinical reports have suggested that mutations or deletions of the HMGA2 gene can be responsible for a SRS-like phenotype in patients with negative results of…
Genome-wide association study of non-alcoholic fatty liver and steatohepatitis in a histologically characterised cohort☆
2020
Background & Aims: Genetic factors associated with nonalcoholic fatty liver disease (NAFLD) remain incompletely understood. To date, most genome-wide association studies (GWASs) have adopted radiologically assessed hepatic triglyceride content as the reference phenotype and so cannot address steatohepatitis or fibrosis. We describe a GWAS encompassing the full spectrum of histologically characterised NAFLD. Methods: The GWAS involved 1,483 European NAFLD cases and 17,781 genetically matched controls. A replication cohort of 559 NAFLD cases and 945 controls was genotyped to confirm signals showing genome-wide or close to genome-wide significance. Results: Case-control analysis identified…
Reduced interneuronal dendritic arborization in CA1 but not in CA3 region of mice subjected to chronic mild stress
2016
Abstract Introduction Chronic stress induces dendritic atrophy and decreases spine density in excitatory hippocampal neurons, although there is also ample evidence indicating that the GABAergic system is altered in the hippocampus after this aversive experience. Chronic stress causes dendritic remodeling both in excitatory neurons and interneurons in the medial prefrontal cortex and the amygdala. Methods In order to know whether it also has an impact on the structure and neurotransmission of hippocampal interneurons, we have analyzed the dendritic arborization, spine density, and the expression of markers of inhibitory synapses and plasticity in the hippocampus of mice submitted to 21 days …
Functional hypoxia drives neuroplasticity and neurogenesis via brain erythropoietin.
2020
Erythropoietin (EPO), named after its role in hematopoiesis, is also expressed in mammalian brain. In clinical settings, recombinant EPO treatment has revealed a remarkable improvement of cognition, but underlying mechanisms have remained obscure. Here, we show with a novel line of reporter mice that cognitive challenge induces local/endogenous hypoxia in hippocampal pyramidal neurons, hence enhancing expression of EPO and EPO receptor (EPOR). High-dose EPO administration, amplifying auto/paracrine EPO/EPOR signaling, prompts the emergence of new CA1 neurons and enhanced dendritic spine densities. Single-cell sequencing reveals rapid increase in newly differentiating neurons. Importantly, i…
Broad neurodevelopmental features and cortical anomalies associated with a novel de novo KMT2A variant in Wiedemann-Steiner syndrome.
2021
Abstract Wiedemann-Steiner syndrome (WDSTS) is a rare genetic disorder including developmental delay/intellectual disability (DD/ID), hypertrichosis cubiti, short stature, and distinctive facial features, caused by mutation in KMT2A gene, which encodes a histone methyltransferase (H3K4) that regulates chromatin-mediated transcription. Different neurodevelopmental phenotypes have been described within the WDSTS spectrum, including a peculiar Autism Spectrum Disorder (ASDs) subtype in some affected individuals. Here, we report a 9-year-old Caucasian male found by next-generation panel sequencing to carry a novel heterozygous de novo KMT2A frameshift variant (NM_001197104.2:c.4433delG; p. Arg1…
Assessment of Targeted Next-Generation Sequencing as a Tool for the Diagnosis of Charcot-Marie-Tooth Disease and Hereditary Motor Neuropathy
2016
Charcot-Marie-Tooth disease is characterized by broad genetic heterogeneity with >50 known disease-associated genes. Mutations in some of these genes can cause a pure motor form of hereditary motor neuropathy, the genetics of which are poorly characterized. We designed a panel comprising 56 genes associated with Charcot-Marie-Tooth disease/hereditary motor neuropathy. We validated this diagnostic tool by first testing 11 patients with pathological mutations. A cohort of 33 affected subjects was selected for this study. The DNAJB2 c.352+1G>A mutation was detected in two cases; novel changes and/or variants with low frequency (50 known disease-associated genes. Mutations in some of these gene…
Temporal profiling of an acute stress-induced behavioral phenotype in mice and role of hippocampal DRR1.
2018
Abstract Understanding the neurobiological mechanisms underlying the response to an acute stressor may provide novel insights into successful stress-coping strategies. Acute behavioral stress-effects may be restricted to a specific time window early after stress-induction. However, existing behavioral test batteries typically span multiple days or even weeks, limiting the feasibility for a broad behavioral analysis following acute stress. Here, we designed a novel comprehensive behavioral test battery in male mice that assesses multiple behavioral dimensions within a sufficiently brief time window to capture acute stress-effects and its temporal profile. Using this battery, we investigated …