38 research outputs found

    A novel approach of homozygous haplotype sharing identifies candidate genes in autism spectrum disorder

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    Autism spectrum disorder (ASD) is a highly heritable disorder of complex and heterogeneous aetiology. It is primarily characterized by altered cognitive ability including impaired language and communication skills and fundamental deficits in social reciprocity. Despite some notable successes in neuropsychiatric genetics, overall, the high heritability of ASD (~90%) remains poorly explained by common genetic risk variants. However, recent studies suggest that rare genomic variation, in particular copy number variation, may account for a significant proportion of the genetic basis of ASD. We present a large scale analysis to identify candidate genes which may contain low-frequency recessive variation contributing to ASD while taking into account the potential contribution of population differences to the genetic heterogeneity of ASD. Our strategy, homozygous haplotype (HH) mapping, aims to detect homozygous segments of identical haplotype structure that are shared at a higher frequency amongst ASD patients compared to parental controls. The analysis was performed on 1,402 Autism Genome Project trios genotyped for 1 million single nucleotide polymorphisms (SNPs). We identified 25 known and 1,218 novel ASD candidate genes in the discovery analysis including CADM2, ABHD14A, CHRFAM7A, GRIK2, GRM3, EPHA3, FGF10, KCND2, PDZK1, IMMP2L and FOXP2. Furthermore, 10 of the previously reported ASD genes and 300 of the novel candidates identified in the discovery analysis were replicated in an independent sample of 1,182 trios. Our results demonstrate that regions of HH are significantly enriched for previously reported ASD candidate genes and the observed association is independent of gene size (odds ratio 2.10). Our findings highlight the applicability of HH mapping in complex disorders such as ASD and offer an alternative approach to the analysis of genome-wide association data

    GWAS meta-analysis of over 29,000 people with epilepsy identifies 26 risk loci and subtype-specific genetic architecture

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    Epilepsy is a highly heritable disorder affecting over 50 million people worldwide, of which about one-third are resistant to current treatments. Here we report a multi-ancestry genome-wide association study including 29,944 cases, stratified into three broad categories and seven subtypes of epilepsy, and 52,538 controls. We identify 26 genome-wide significant loci, 19 of which are specific to genetic generalized epilepsy (GGE). We implicate 29 likely causal genes underlying these 26 loci. SNP-based heritability analyses show that common variants explain between 39.6% and 90% of genetic risk for GGE and its subtypes. Subtype analysis revealed markedly different genetic architectures between focal and generalized epilepsies. Gene-set analyses of GGE signals implicate synaptic processes in both excitatory and inhibitory neurons in the brain. Prioritized candidate genes overlap with monogenic epilepsy genes and with targets of current antiseizure medications. Finally, we leverage our results to identify alternate drugs with predicted efficacy if repurposed for epilepsy treatment

    Genome-wide identification and phenotypic characterization of seizure-associated copy number variations in 741,075 individuals

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    Copy number variants (CNV) are established risk factors for neurodevelopmental disorders with seizures or epilepsy. With the hypothesis that seizure disorders share genetic risk factors, we pooled CNV data from 10,590 individuals with seizure disorders, 16,109 individuals with clinically validated epilepsy, and 492,324 population controls and identified 25 genome-wide significant loci, 22 of which are novel for seizure disorders, such as deletions at 1p36.33, 1q44, 2p21-p16.3, 3q29, 8p23.3-p23.2, 9p24.3, 10q26.3, 15q11.2, 15q12-q13.1, 16p12.2, 17q21.31, duplications at 2q13, 9q34.3, 16p13.3, 17q12, 19p13.3, 20q13.33, and reciprocal CNVs at 16p11.2, and 22q11.21. Using genetic data from additional 248,751 individuals with 23 neuropsychiatric phenotypes, we explored the pleiotropy of these 25 loci. Finally, in a subset of individuals with epilepsy and detailed clinical data available, we performed phenome-wide association analyses between individual CNVs and clinical annotations categorized through the Human Phenotype Ontology (HPO). For six CNVs, we identified 19 significant associations with specific HPO terms and generated, for all CNVs, phenotype signatures across 17 clinical categories relevant for epileptologists. This is the most comprehensive investigation of CNVs in epilepsy and related seizure disorders, with potential implications for clinical practice

    Una tecnica innovativa ed efficiente per gestire lo scenario floristico presente sulla banchina stradale

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    La manutenzione del patrimonio stradale comprende anche l'intervento di sfalcio della vegetazione erbacea e arbustiva lungo le banchine e le relative pertinenze (quali cigli e scarpate). Questo servizio è fondamentale per il decoro del territorio, ma sopratutto per la sicurezza dei cittadini, per garantire la fruizione della carreggiata e per non ostacolare la visibilità della segnaletica orizzontale e verticale. E' noto altresì come l'incontrollato proliferare delle erbe infestanti porti all'intasamento delle cunette e dei sistemi di raccolta ed evacuazione delle acque meteoriche. Inoltre, la presenza di masse vegetali secche si associa a enormi rischi di incendio, oltre che implicare aspetti problematici di ordine igienico-sanitario. Al contrario, un cotico erboso possibilmente polifita, con prevalenza, garantisce la protezione delle scarpate da fenomeni di erosione e provvede alla rimozione di inquinanti aerodispersi. Storicamente, il compito di tenere sotto controllo la vegetazione spontanea presente lungo le banchine stradali è stato affidato a periodici interventi meccanici di sfalcio.Tali operazioni sipresentano come particolarmente impattanti sulle comunità biologiche, richiedono organizzazioni logistiche non banali e sono impegnative sotto il profilo economico; analoghe considerazioni sono valide per i metodi basati sull'impiego del calore e della fiamma, preoccupanti in quanto capaci di provocare traumi ambientali di non poco momento. Una soluzione che coniuga già nel medio periodo convenienza di bilancio, ecosostenibilità, qualità del risultato anche in termini paesaggistici è la costituzione e il successivo mantenimento di un fitto ed equilibrato consorzio erbaceo permanente con le caratteristiche appena descritte. Ciò è possibile con un numero ridotto di interventi chimici selettivi, finalizzati al vivace contrasto alla vegetazione concorrente rispetto a gramigna e convolvolo, per dare spazio a queste due specie, notoriamente capaci di garantire una copertura equilibrata, stabile e di basso profilo verticale. Uno dei prodotti da tempo utilizzati per tale scopo, noto con il nome commerciale di Rodeo Gold, contiene glifosato, senza aggiunta di tensioattivi e/o coformulanti. L'uso è autorizzato dal mistero della salute. Il prodotto è da considerarsi sicuro nei confronti di operatori, cittadini, animali domestici, fauna e ambiente in genere, non è volatile, non si muove nel terreno nè in orizzontale nè in in verticale, si degrada velocemente nel suolo in sostanze riconosciute dalla natura e quindi non inquina e sfugge ai fenomeni di bioaccumulo; viene assorbito solo dalle foglie e non interferisce nè con lo sviluppo radicale nè con la germinabilità dei semi presenti nel terreno. Il presente volume descrive le attività sperimentali svolte in un biennio in condizioni di piena aderenza alla realtà e finalizzate alla valutazione di parametri biologici, chimici ed ecologici in un test di confronto tra trattamenti convenzionali (sfalcio meccanico) e applicazioni di Rodeo gold

    Shedding light on dark genes: enhanced targeted resequencing by optimizing the combination of enrichment technology and DNA fragment length

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    The exome contains many obscure regions difficult to explore with current short-read sequencing methods. Repetitious genomic regions prevent the unique alignment of reads, which is essential for the identification of clinically-relevant genetic variants. Long-read technologies attempt to resolve multiple-mapping regions, but they still produce many sequencing errors. Thus, a new approach is required to enlighten the obscure regions of the genome and rescue variants that would be otherwise neglected. This work aims to improve the alignment of multiple-mapping reads through the extension of the standard DNA fragment size. As Illumina can sequence fragments up to 550\u2009bp, we tested different DNA fragment lengths using four major commercial WES platforms and found that longer DNA fragments achieved a higher genotypability. This metric, which indicates base calling calculated by combining depth of coverage with the confidence of read alignment, increased from hundreds to thousands of genes, including several associated with clinical phenotypes. While depth of coverage has been considered crucial for the assessment of WES performance, we demonstrated that genotypability has a greater impact in revealing obscure regions, with ~1% increase in variant calling in respect to shorter DNA fragments. Results confirmed that this approach enlightened many regions previously not explored

    Higher levels of IgA and IgG at sepsis onset are associated with higher mortality: results from the Albumin Italian Outcome Sepsis (ALBIOS) trial

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    Background: The role of intravenous immunoglobulins (IVIG) during sepsis is controversial, as different trials on IVIG have observed inconsistent survival benefits. We aimed to elucidate the possible association and clinical significance between circulating levels of immunoglobulins. Methods: In a subset of 956 patients with severe sepsis and septic shock of the multicentre, open-label RCT ALBIOS, venous blood samples were serially collected 1, 2, and 7 days after enrolment (or at ICU discharge, whichever came first). IgA, IgG and IgM concentrations were assayed in all patients on day 1 and in a subgroup of 150 patients on days 2 and 7. Ig concentrations were measured employing a turbidimetric assay, OSR61171 system. Results: IgA on day 1 had a significant predictive value for both 28-day and 90-day mortality (28-day mortality, HR: 1.50 (95% CI 1.18-1.92); 90-day mortality, HR: 1.54 (95% CI 1.25-1.91)). IgG, but not IgM, on day 1 showed similar results for 28-day (HR 1.83 (95% CI 1.33-2.51) and 90-day mortality HR: 1.66 (95% CI 1.23-2.25)). In addition, lower levels of IgG but not of IgA and IgM, at day 1 were associated with significantly higher risk of secondary infections (533 [406-772] vs 600 [452-842] mg/dL, median [Q1-Q3], p = 0.007). Conclusions: In the largest cohort study of patients with severe sepsis or septic shock, we found that high levels of IgA and IgG on the first day of diagnosis were associated with a decreased 90-day survival. No association was found between IgM levels and survival. As such, the assessment of endogenous immunoglobulins could be a useful tool to identify septic patients at high risk of mortality. Trial registration #NCT00707122, Clinicaltrial.gov, registered 30 June 2008
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