Publications by authors named "Julian Willett"

Genomics for rare disease diagnosis has advanced at a rapid pace due to our ability to perform in-depth analyses on individual patients with ultra-rare diseases. The increasing sizes of ultra-rare disease cohorts internationally newly enables cohort-wide analyses for new discoveries, but well-calibrated statistical genetics approaches for jointly analyzing these patients are still under development. The Undiagnosed Diseases Network (UDN) brings multiple clinical, research and experimental centers under the same umbrella across the United States to facilitate and scale case-based diagnostic analyses.

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The identification of Alzheimer's disease (AD)-associated genomic variants has provided powerful insight into disease etiology. Genome-wide association studies (GWASs) of AD have successfully identified previously unidentified targets but have almost exclusively used additive genetic models. Here, we performed a family-based GWAS of a recessive inheritance model using whole-genome sequencing from families affected by AD.

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The identification of Alzheimer's disease (AD)-associated genomic variants has provided powerful insight into disease etiology. Genome-wide association studies (GWAS) for AD have successfully identified new targets but have almost exclusively utilized additive genetic models. Here, we performed a family-based GWAS under a recessive inheritance model using whole genome sequencing from families affected by AD.

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Introduction: Alzheimer's disease (AD) is the most prevalent form of dementia. While many AD-associated genetic determinants have been identified, few studies have analyzed individuals of non-European ancestry.

Methods: We conducted a multi-ancestry genome-wide association study (GWAS) of clinically diagnosed AD and AD-by-proxy using whole genome sequencing data from the National Institute on Aging Genetics of Alzheimer's Disease Data Storage Site (NIAGADS), National Institute of Mental Health, UK Biobank (UKB), and All of Us (AoU) consisting of 49,149 cases (12,074 clinically diagnosed and 37,075 AD-by-proxy) and 383,225 controls.

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Alzheimer's disease (AD) is the most common form of dementia in elderly, affecting 6.9 million individuals in the United States. Some studies have suggested the prevalence of AD is greater in individuals who self-identify as Hispanic.

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Obesity strongly increases the risk of cardiometabolic diseases, yet the underlying mediators of this relationship are not fully understood. Given that obesity strongly influences circulating protein levels, we investigated proteins mediating the effects of obesity on coronary artery disease, stroke and type 2 diabetes. By integrating two-step proteome-wide Mendelian randomization, colocalization, epigenomics and single-cell RNA sequencing, we identified five mediators and prioritized collagen type VI α3 (COL6A3).

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Article Synopsis
  • Alzheimer's disease is a leading form of dementia in older adults, and early detection is crucial for effective intervention since its effects can begin decades before symptoms show.
  • The study utilized advanced machine learning techniques to create models predicting Alzheimer's status and onset age, analyzing a range of biological and medical data from UK Biobank, with significant emphasis on the importance of specific proteins.
  • Notable findings include that GFAP and CXCL17 proteins are strong predictors of Alzheimer's, while genomics and proteomics provided the most valuable information in predicting disease status, although expanding the dataset with "AD-by-proxy" cases didn't enhance prediction accuracy.
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Article Synopsis
  • Alzheimer's disease (AD) is the most common form of dementia, and while many genetic factors have been found, research has mostly focused on people of European descent.
  • This study analyzed whole genome sequencing data from a diverse group of participants (about 49,000 AD cases and 383,000 controls) to identify new genetic loci associated with AD.
  • The researchers discovered 16 novel loci linked to clinically-diagnosed AD and AD-by-proxy, emphasizing the need for more diverse studies in genetic research.
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Article Synopsis
  • Recent advancements in genomics for diagnosing rare diseases focus on "N-of-1" analyses, allowing for tailored studies on individual patients with ultra-rare conditions.
  • The Undiagnosed Diseases Network (UDN) enables collaborative research across various U.S. clinical and research centers, which enhances the ability to analyze whole genome sequencing data from multiple patients simultaneously.
  • Introducing a new software package, RaMeDiES, the team provides tools for automated comparisons of genomic data, leading to novel disease associations and improving overall understanding of genetic links to these rare diseases.
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The persistence of SARS-CoV-2 despite the development of vaccines and a degree of herd immunity is partly due to viral evolution reducing vaccine and treatment efficacy. Serial infections of wild-type (WT) SARS-CoV-2 in Balb/c mice yield mouse-adapted strains with greater infectivity and mortality. We investigate if passaging unmodified B.

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Alternative splicing generates functional diversity in isoforms, impacting immune response to infection. Here, we evaluate the causal role of alternative splicing in COVID-19 severity and susceptibility by applying two-sample Mendelian randomization to cis-splicing quantitative trait loci and the results from COVID-19 Host Genetics Initiative. We identify that alternative splicing in lung, rather than total expression of OAS1, ATP11A, DPP9 and NPNT, is associated with COVID-19 severity.

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Identifying causal genes at GWAS loci can help pinpoint targets for therapeutic interventions. Expression studies can disentangle such loci but signals from expression quantitative trait loci (eQTLs) often fail to colocalize-which means that the genetic control of measured expression is not shared with the genetic control of disease risk. This may be because gene expression is measured in the wrong cell type, physiological state, or organ.

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Article Synopsis
  • * A study screened nearly 5,000 plasma proteins and identified 1,216 influenced by body mass index, discovering nephronectin (NPNT) as a key protein linked to worse COVID-19 outcomes.
  • * NPNT was found to be expressed in lung cells of those who died from COVID-19 and was linked to increased illness severity, suggesting that managing body fat could lower NPNT levels and potentially improve COVID-19 outcomes.
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Metabolic processes can influence disease risk and provide therapeutic targets. By conducting genome-wide association studies of 1,091 blood metabolites and 309 metabolite ratios, we identified associations with 690 metabolites at 248 loci and associations with 143 metabolite ratios at 69 loci. Integrating metabolite-gene and gene expression information identified 94 effector genes for 109 metabolites and 48 metabolite ratios.

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Despite two years of intense global research activity, host genetic factors that predispose to a poorer prognosis of COVID-19 infection remain poorly understood. Here, we prioritise eight robust (e.g.

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In this study, we describe the experiments determining whether coating gold nanoparticles with tetraethylene glycol (TEG) provides pharmacologically relevant advantages, such as increased serum half-life and resistance to protein adsorption. Monodisperse TEG-coated, NaBH-reduced gold nanoparticles with a hydrodynamic size comparable to albumin were synthesized by reducing gold chloride with NaBH under alkaline conditions in the presence of TEG-SH. The particles were characterized by gel electrophoresis, column chromatography, and transmission electron microscopy.

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How the kidney prevents urinary excretion of plasma proteins continues to be debated. Here, using unfixed whole-mount mouse kidneys, we show that fluorescent-tagged proteins and neutral dextrans permeate into the glomerular basement membrane (GBM), in general agreement with Ogston's 1958 equation describing how permeation into gels is related to molecular size. Electron-microscopic analyses of kidneys fixed seconds to hours after injecting gold-tagged albumin, negatively charged gold nanoparticles, and stable oligoclusters of gold nanoparticles show that permeation into the lamina densa of the GBM is size-sensitive.

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