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Farrall, M.

Publications and source records attributed to Farrall, M..

2 recordsLinked to original sources

Enhanced prediction of gene and missense rare-variant pathogenicity by joint analysis of gene burden and amino-acid residue position

BackgroundAlthough rare-missense variants in Mendelian disease-genes have been noted to cluster in specific regions of proteins, it is not clear how to consider this information when evaluating the pathogenicity of a gene or variant. Here we introduce methods for gene-association and variant-interpretation that utilise this powerful signal. MethodsWe present a case-control rare-variant association test, ClusterBurden, that combines information on both variant-burden and variant-clustering. We then introduce a data-driven modelling framework to estimate mutational hotspots in genes with missense variant-clustering and integrate further in-silico predictors into the models. ResultsWe show that ClusterBurden can increase statistical power to scan for putative disease-genes, driven by missense variants, in simulated data and a 34-gene panel dataset of 5,338 cases of hypertrophic cardiomyopathy. We demonstrate that data-driven models can allow quantitative application of the ACMG criteria PM1 and PP3, to resolve a wide range of pathogenicity potential amongst variants of uncertain significance. A web application (Pathogenicity_by_Position) is accessible for missense variant risk prediction of six sarcomeric genes and an R package is available for association testing using ClusterBurden. ConclusionThe inclusion of missense residue position enhances the power of disease-gene association and improves rare-variant pathogenicity interpretation.

genetics

Heritability and family-based GWAS analyses of the N-acyl ethanolamine and ceramide lipidome reveal genetic influence over circulating lipids

Signalling lipids of the N-acyl ethanolamine (NAE) and ceramide (CER) classes are emerging as novel cardiovascular disease biomarkers. We sought to establish the heritability of plasma NAEs (including the endocannabinoid anandamide) and CERs, and identify common DNA variants influencing the circulating concentrations of the heritable lipid species. Nine NAE and sixteen CER species were analysed in plasma samples from 999 members of 196 British Caucasian families, using targeted mass spectrometry (UPLC-MS/MS). Heritability was estimated and GWAS analyses were undertaken; all target lipids were significantly heritable (h2 = 36%-62%). A missense variant (rs324420) in the gene encoding the enzyme fatty acid amide hydrolase (FAAH), which degrades NAEs, associated at GWAS significance (P<2.15x10-8) with four NAEs (DHEA, PEA, LEA, VEA). The A allele of this SNP was associated with a 0.23 SD per-allele increase in plasma NAE species. Additionally, we found association between rs680379 in the SPTLC3 gene, which encodes a subunit of the rate limiting enzyme in CER biosynthesis, and a range of CER species (e.g. CER[N(24)S(19)]; P =4.82x10-27). We also observed three novel associations (CD83, SGPP1, FBXO28-DEGS1) influencing plasma CER traits, two of which (SGPP1 and DEGS1) implicate CER species in haematological phenotypes. NAE and CER are substantially heritable bioactive lipids, influenced by SNPs in key metabolic enzymes.

genetics