Publications by authors named "Raybould R"

Alzheimer's disease (AD), the leading cause of dementia, has an estimated heritability of approximately 70%. The genetic component of AD has been mainly assessed using genome-wide association studies, which do not capture the risk contributed by rare variants. Here, we compared the gene-based burden of rare damaging variants in exome sequencing data from 32,558 individuals-16,036 AD cases and 16,522 controls.

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A strategy to gain insight into early changes that may predispose people to Alzheimer's disease (AD) is to study the brains of younger cognitively healthy people that are at increased genetic risk of AD. The Apolipoprotein (APOE) E4 allele is the strongest genetic risk factor for AD, and several neuroimaging studies comparing APOE E4 carriers with non-carriers at age ∼20-30 years have detected hyperactivity (or reduced deactivation) in posteromedial cortex (PMC), a key hub of the default network (DN), which has a high susceptibility to early amyloid deposition in AD. Transgenic mouse models suggest such early network activity alterations may result from altered excitatory/inhibitory (E/I) balance, but this is yet to be examined in humans.

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Background: Proximal tubular cells (PTCs) are the most abundant cell type in the kidney. PTCs are central to normal kidney function and to regeneration versus organ fibrosis following injury. This study used single-nucleus RNA sequencing (snRNAseq) to describe the phenotype of PTCs in renal fibrosis.

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Sporadic Alzheimer's disease (AD) is a complex genetic disease, and the leading cause of dementia worldwide. Over the past 3 decades, extensive pioneering research has discovered more than 70 common and rare genetic risk variants. These discoveries have contributed massively to our understanding of the pathogenesis of AD but approximately half of the heritability for AD remains unaccounted for.

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Prion diseases are fatal and transmissible neurodegenerative disorders caused by the misfolding and aggregation of prion protein. Although recent studies have implicated epigenetic variation in common neurodegenerative disorders, no study has yet explored their role in human prion diseases. Here we profiled genome-wide blood DNA methylation in the most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD).

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To determine the relationship between psychological stress with cognitive outcomes in a multi-centre longitudinal study of people with amnestic mild cognitive impairment (aMCI) we assessed three parameters of psychological stress (Recent Life Changes Questionnaire (RLCQ); the Perceived Stress Scale (PSS) and salivary cortisol) and their relationship with rates of cognitive decline over an 18 month follow up period and conversion to dementia over a 5.5 year period. In 133 aMCI and 68 cognitively intact participants the PSS score was higher in the aMCI compared with control group but neither the RLCQ scores nor salivary cortisol measures were different between groups.

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  • An amendment to the original paper has been released.
  • You can find the amendment through a link provided at the top of the paper.
  • This update may contain important changes or additional information related to the original content.
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  • Late-onset Alzheimer's disease (LOAD) is the most common type of dementia and is influenced by genetics.
  • Researchers studied a lot of people (94,437) to find specific genes that may increase the risk of developing LOAD, confirming 20 known ones and discovering 5 new ones.
  • They also found that certain genetic traits related to the immune system and how the brain processes proteins are linked to a higher risk of LOAD, suggesting there are more rare genes yet to be identified that could also play a role.
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Next-generation genetic sequencing (NGS) technologies facilitate the screening of multiple genes linked to neurodegenerative dementia, but there are few reports about their use in clinical practice. Which patients would most profit from testing, and information on the likelihood of discovery of a causal variant in a clinical syndrome, are conspicuously absent from the literature, mostly for a lack of large-scale studies. We applied a validated NGS dementia panel to 3241 patients with dementia and healthy aged controls; 13,152 variants were classified by likelihood of pathogenicity.

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Article Synopsis
  • * Our research uncovered three significant variants: a protective variant in the PLCG2 gene and risk variants in ABI3 and TREM2, known for their roles in Alzheimer's susceptibility.
  • * The findings emphasize the importance of microglia, immune cells in the brain, suggesting that their genetic variations may contribute directly to the progression of Alzheimer's disease.
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Periodontitis is common in the elderly and may become more common in Alzheimer's disease because of a reduced ability to take care of oral hygiene as the disease progresses. Elevated antibodies to periodontal bacteria are associated with an increased systemic pro-inflammatory state. Elsewhere raised serum pro-inflammatory cytokines have been associated with an increased rate of cognitive decline in Alzheimer's disease.

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Objectives: To determine whether the tumor necrosis factor α inhibitor etanercept is well tolerated and obtain preliminary data on its safety in Alzheimer disease dementia.

Methods: In a double-blind study, patients with mild to moderate Alzheimer disease dementia were randomized (1:1) to subcutaneous etanercept (50 mg) once weekly or identical placebo over a 24-week period. Tolerability and safety of this medication was recorded including secondary outcomes of cognition, global function, behavior, and systemic cytokine levels at baseline, 12 weeks, 24 weeks, and following a 4-week washout period.

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Background: Methylation of HPV16 DNA is a promising biomarker for triage of HPV positive cervical screening samples but the biological basis for the association between HPV-associated neoplasia and increased methylation is unclear.

Objectives: To determine whether HPV16 DNA methylation was associated with viral integration, and investigate the relationships between viral DNA methylation, integration and gene expression.

Study Design: HPV16 DNA methylation, integration and gene expression were assessed using pyrosequencing, ligation-mediated PCR and QPCR, in biopsies from 25 patients attending a specialist vulval neoplasia clinic and in short-term clonal cell lines derived from vulval and vaginal neoplasia.

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Vulval intraepithelial neoplasia is a precursor of vulval cancer and is commonly caused by infection with Human Papillomavirus (HPV). Development of topical treatments for vulval intraepithelial neoplasia requires appropriate in vitro models. This study evaluated the feasibility of primary culture of vulval intraepithelial neoplasia biopsy tissue to produce cell lines for use as in vitro models.

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Human Papillomavirus (HPV) infection is the primary cause of cervical neoplasia. HPV DNA is integrated into the human genome in the majority of cervical cancers. The nature of integration may differ with integration incorporating a single copy of HPV or occurring in concatenated form.

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We previously performed a linkage study using families identified through probands meeting criteria for DSM-IV schizoaffective disorder, bipolar type (SABP) and observed a genome-wide significant signal (LOD = 3.54) at chromosome 1q42 close to DISC1. An initial sequencing study of DISC1 using 14 unrelated DSM-IV SABP samples from the linkage study identified 2 non-synonymous coding SNPs in exon 11 in 2 separate individuals.

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The chromosomal region 12q24 has been previously implicated by linkage studies of both bipolar disorder and unipolar mood disorder and we have reported two pedigrees segregating both bipolar disorder and Darier's disease that show linkage across this region. The gene P2RX7 is located in this chromosomal region and has been recently reported as a susceptibility gene for bipolar disorder and unipolar depression. The non-synonymous SNP rs2230912 (resulting in amino-acid polymorphism Q460R) showed the strongest association and has been postulated to be pathogenically relevant.

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A surveillance study designed to provide a representative sample of the strains of Clostridium difficile causing infections in hospitals in England was in operation from April 2007 to the end of March 2008. Six hundred and seventy-seven isolates were obtained from 186 hospitals in the nine geographical regions of England as recognised by the Health Protection Agency's Regional Microbiology Network. Typing studies revealed that PCR ribotype 027 is now the most common strain isolated from symptomatic patients, accounting for over 41.

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Context: Variation at the DAOA/G30 locus has been described to be associated with both schizophrenia and bipolar disorder, but there is little consistency between studies of the tested polymorphisms or variants showing association.

Objectives: To obtain a stringent replication of association in large samples of both disorders using consistent clinical and laboratory methods, and to test the hypothesis that association at DAOA/G30 identifies an underlying domain of psychopathological abnormalities that cuts across traditional diagnostic categories.

Design: A systematic study of polymorphisms at DAOA/G30 using genetic case-control association analysis.

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Background: Brain-derived neurotrophic factor (BDNF) influences neuronal survival, proliferation and plasticity. Three family-based studies have shown association of the common Valine (Val) allele of the Val66Met polymorphism of the BDNF gene with susceptibility to bipolar disorder.

Aims: To replicate this finding.

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Bipolar affective disorder (BPAD) is a common psychiatric disorder with complex genetic aetiology. We have undertaken a genome-wide scan in one of the largest samples of bipolar affected sibling pairs (ASPs) using a two-stage approach combining sample splitting and marker grid tightening. In this second stage analysis, we have examined 17 regions that achieved a nominally significant maximum likelihood LOD score (MLS) threshold of 0.

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Attention deficit hyperactivity disorder (ADHD) is a common, highly heritable, neurodevelopmental disorder with onset in early childhood. Genes involved in neuronal development and growth are, thus, important etiological candidates and brain-derived neurotrophic factor (BDNF), has been hypothesized to play a role in the pathogenesis of ADHD. BDNF is a member of the neurotrophin family and is involved in the survival and differentiation of dopaminergic neurons in the developing brain (of relevance because drugs that block the dopamine transporter can be effective therapeutically).

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Context: Family and twin data suggest that, in addition to susceptibility genes specific for bipolar disorder or schizophrenia, genes exist that contribute to susceptibility across the traditional kraepelinian divide. Several studies have provided evidence that variation at the neuregulin 1 (NRG1) gene on chromosome 8p12 influences susceptibility to schizophrenia. The most consistent finding has been that one particular haplotype (the "core" haplotype) is overrepresented in cases compared with control subjects.

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Background: Several studies support the dysbindin (dystrobrevin binding protein 1) gene (DTNBP1) as a susceptibility gene for schizophrenia. We previously reported that variation at a specific 3-locus haplotype influences susceptibility to schizophrenia in a large United Kingdom (UK) Caucasian case-control sample.

Methods: Using similar methodology to our schizophrenia study, we have investigated this same 3-locus haplotype in a large, well-characterized bipolar sample (726 Caucasian UK DSM-IV bipolar I patients; 1407 ethnically matched controls).

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