Biology subjects

Bowes, J.

Publications and source records attributed to Bowes, J..

6 recordsLinked to original sources

bioRxiv2023

A cis-regulatory element regulates ERAP2 expression through autoimmune disease risk SNPs

Single nucleotide polymorphisms (SNP) near the ERAP2 gene are associated with autoimmune conditions such as Crohns disease, and birdshot chorioretinopathy, as well as protection against lethal infections, including the Black Death. Due to high linkage disequilibrium (LD), a great number of trait-associated SNPs are correlated with ERAP2 expression, however their functional mechanisms remain unidentified. We used genome editing and functional genomics to identify causal variants that remain obscured by LD. We demonstrate by reciprocal allelic replacement that ERAP2 expression is directly controlled by the genotype of splice region SNP rs2248374. However, we demonstrate that autoimmune disease-risk SNPs located near the downstream LNPEP gene promoter are independently associated with ERAP2 expression. Allele-specific conformation capture assays revealed long-range chromatin contacts between the LNPEP promoter region and the ERAP2 promoter and showed that interactions were stronger in patients carrying the alleles that increase susceptibility to autoimmune diseases. Replacing the disease-associated SNPs in the LNPEP promoter by reference sequences lowered ERAP2 expression. These findings show that clustered GWAS signals associated with diverse autoimmune conditions and lethal infections act in concert to control ERAP2 expression and that disease-associated variants can convert a gene promoter region into a potent enhancer of a distal gene.

genomics↗

bioRxiv2022

Identification of a regulatory pathway governing TRAF1 via an arthritis-associated non-coding variant

TRAF1/C5 was among the first loci shown to confer risk for inflammatory arthritis in the absence of an associated coding variant, but its genetic mechanism remains undefined. Using ImmunoChip data from 3,939 juvenile idiopathic arthritis (JIA) patients and 14,412 controls, we identified 132 plausible common non-coding variants, reduced serially by SNP-seq, electrophoretic mobility shift, and luciferase studies to the single variant rs7034653 in the third intron of TRAF1. Genetically manipulated experimental cells and primary monocytes from genotyped donors establish that the risk G allele reduces binding of Fos-Related Antigen 2 (FRA2), resulting in reduced TRAF1 expression and enhanced TNF production. Conditioning on this variant eliminates attributable risk for rheumatoid arthritis, implicating a mechanism shared across the arthritis spectrum. These findings reveal that rs7034653, FRA2, and TRAF1 mediate a pathway through which a non-coding causal variant drives risk of inflammatory arthritis in children and adults.

genetics↗

bioRxiv2020

Characterisation of the genetic architecture of immune-mediated disease through informed dimension reduction

Integration of genome-wide association study (GWAS) data has been used to generate new hypotheses of biological mechanism, aetiological relationships between traits, or test causality of one factor for another. However, such approaches have typically been limited to pairwise comparisons of traits. We propose a generally applicable method, that exploits ideas from Bayesian genetic fine mapping to define a "lens" that focuses relevant variants before dimension reduction of a set of related GWAS summary statistics. We applied this technique to immune-mediated diseases, deriving 13 components which summarise the multidimensional patterns of genetic risk. Projection of independent datasets demonstrated the specificity and accuracy of our reduced dimension basis, enabled us to functionally characterise individual components, identify disease-discriminating components and suggest novel associations in rare diseases where classical GWAS approaches are challenging. Our approach summarises the genetic architectures underlying any range of aetiologically-related traits in fewer dimensions, facilitating more nuanced multidimensional comparative analyses.

genetics↗

bioRxiv2019

Exploring the overlap between rheumatoid arthritis susceptibility loci and long non-coding RNA annotations

Whilst susceptibility variants for many complex diseases, such as rheumatoid arthritis (RA), have been well characterised, the mechanism by which risk is mediated is still unclear for many loci. This is especially true for the majority of variants that do not affect protein-coding regions. lncRNA represent a group of molecules that have been shown to be enriched amongst variants associated with RA and other complex diseases, compared to random variants. In order to establish to what degree direct disruption of lncRNA may represent a potential mechanism for mediating RA susceptibility, we chose to further explore this overlap. By testing the ability of annotated features to improve a model of disease susceptibility, we were able to demonstrate a local enrichment of enhancers from immune-relevant cell types amongst RA susceptibility variants (log2 enrichment 3.40). This was not possible for lncRNA annotations in general, however a small, but significant enrichment was observed for immune-enriched lncRNA (log2 enrichment 0.867002). This enrichment was no longer apparent when the model was conditioned on immune-relevant enhancers (log2 enrichment -0.372734), suggesting that direct disruption of lncRNA sequence, independent of enhancer disruption, does not represent a major mechanism by which susceptibility to complex diseases is mediated. Furthermore, we demonstrated that, in keeping with general lncRNA characteristics, immune-enriched lncRNA are expressed at low levels that may not be amenable to functional characterisation.

genetics↗

bioRxiv2019

Selective constraints and pathogenicity of mitochondrial DNA variants inferred from a novel database of 196,554 unrelated individuals

High quality population allele frequencies of DNA variants can be used to discover new biology, and study rare disorders. Here, we created a public catalog of mitochondrial DNA variants based on a population of 195,983 individuals. We focused on 3 criteria: (i) the population is not enriched for mitochondrial disorders, or other clinical phenotypes, (ii) all genomes are sequenced and analyzed in the same clinical laboratory, and (iii) both homoplasmic and heteroplasmic variants are reported. We found that 47% of the mitochondrial genome was invariant in this population, including large stretches in the 2 rRNA genes. This information could be used to annotate the mitochondrial genome in future studies. We also showed how to use this resource for the interpretation of pathogenic variants for rare mitochondrial disorders. For example, 42% of variants previously reported to be pathogenic for Leber Hereditary Optic Neuropathy (LHON) should be reclassified.

genetics↗

bioRxiv2019

Population Health Genetic Screening for Tier 1 Inherited Diseases in Northern Nevada: 90% of At-Risk Carriers are Missed

In an unselected population of 23,713 participants who underwent clinical exome sequencing as a part of the Healthy Nevada Project (HNP) in Northern Nevada (Renown Health, Reno, Nevada) from March 15, 2018, to Sept 30, 2018 (Table S1) we find a 1.26% carrier rate for expected pathogenic and likely pathogenic genetic variants in (FH: LDLR, PCSK9, APOB), Hereditary Breast and Ovarian Cancer (HBOC: BRCA1, BRCA2) and Lynch Syndrome (LS: MLH1, MSH2, MSH6, PSM2) with over 90% of carriers undetected under current medical practice. 26% of carriers were found to have advanced disease with 70% first diagnosed before the age of 65. Less than 20% of all carriers had any documented suspicion for inherited genetic disease in the medical record and upon direct follow-up survey under 40% of carriers had family history of relevant disease. A population preventative genetic screening approach for patients under 45 may improve outcomes.\n\nO_TBL View this table:\norg.highwire.dtl.DTLVardef@1eb1896org.highwire.dtl.DTLVardef@19b2a11org.highwire.dtl.DTLVardef@1e6da81org.highwire.dtl.DTLVardef@1138699org.highwire.dtl.DTLVardef@e9c415_HPS_FORMAT_FIGEXP M_TBL O_FLOATNOTable S1:C_FLOATNO O_TABLECAPTIONDemographic Profile of Healthy Nevada Project Participants.\n\nC_TABLECAPTION C_TBL

genetics↗