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Biology subjects

Fearnley, L. G.

Publications and source records attributed to Fearnley, L. G..

3 recordsLinked to original sources

Ultrafast, alignment-free detection of repeat expansions in NGS and RNAseq data

Short tandem repeat expansions are an established cause of diseases such as Huntingtons disease. Bioinformatic methods for detecting repeat expansions in short-read sequencing have revealed new repeat expansions in humans. Current bioinformatic methods to detect repeat expansions require alignment information to identify repetitive motif enrichment at genomic locations. We present superSTR, an ultrafast method that does not require alignment. We demonstrate superSTRs ability to efficiently process both whole-genome and whole-exome sequencing data. Using superSTR we perform the first analysis of the UK Biobank to efficiently screen the exomes of 49,953 biobank participants for repeat expansions. We identify known mutations, as well as diseases not previously associated with REs. We further demonstrate the first bioinformatic screening of RNA sequencing data to detect repeat expansions in patients with spinocerebellar ataxia and Fuchs endothelial corneal dystrophy, and mouse models of myotonic dystrophy. superSTR is a highly computationally-efficient repeat expansion tool screening and detection tool for genomewide novel repeat expansion analysis, significantly outperforming existing methods. superSTR is available from https://github.com/bahlolab/superSTR.

bioinformatics↗

Activation-induced re-organization of chromatin in human T cells

Remodelling of chromatin architecture is known to regulate gene expression and has been well characterized in cell lineage development but less so in response to cell perturbation. Activation of T cells, which triggers extensive changes in transcriptional programs, serves as an instructive model to elucidate how changes in genome organization orchestrate gene expression in response to cell perturbation. To characterize coordinate changes at different levels of chromatin architecture, we analysed chromatin accessibility, chromosome conformation and gene expression after activation of human T cells. T cell activation led to widespread changes in chromatin interactions and accessibility that were mostly shared between CD4+ and CD8+ T cells. Differential chromatin interactions were associated with upregulation or downregulation of linked target genes. Moreover, activation was associated with the formation of shorter chromatin interactions, partitioning of topologically associating domains (TADs) and acquisition of new TAD boundaries characterized by higher nucleosome occupancy, and lower chromatin accessibility and gene expression. These findings render an integrated and multiscale characterization of activation-induced re-organization of chromatin architecture underlying gene transcription in human T cells.

genetics↗

An interaction map of circulating metabolites, immune gene networks and their genetic regulation

The interaction between metabolism and the immune system plays a central role in many cardiometabolic diseases. We integrated blood transcriptomic, metabolomic, and genomic profiles from two population-based cohorts, including a subset with 7-year follow-up sampling. We identified topologically robust gene networks enriched for diverse immune functions including cytotoxicity, viral response, B cell, platelet, neutrophil, and mast cell/basophil activity. These immune gene modules showed complex patterns of association with 158 circulating metabolites, including lipoprotein subclasses, lipids, fatty acids, amino acids, and CRP. Genome-wide scans for module expression quantitative trait loci (mQTLs) revealed five modules with mQTLs of both cis and trans effects. The strongest mQTL was in ARHGEF3 (rs1354034) and affected a module enriched for platelet function. Mast cell/basophil and neutrophil function modules maintained their metabolite associations during 7-year follow-up, while our strongest mQTL in ARHGEF3 also displayed clear temporal stability. This study provides a detailed map of natural variation at the blood immuno-metabolic interface and its genetic basis, and facilitates subsequent studies to explain inter-individual variation in cardiometabolic disease.

genomics↗