bioRxiv ScienceSearch

Biology subjects

Philippe Goyette

Publications and source records attributed to Philippe Goyette.

2 recordsLinked to original sources

A protein truncating R179X variant in RNF186 confers protection against ulcerative colitis

We conducted a search for protein truncating variants conferring protection against inflammatory bowel disease exploiting knowledge of common variants associated with the same disease. We found that a protein truncating variant (rs36095412, p.R179X, genotyped in 11,148 ulcerative colitis patients and 295,446 controls, MAF = up to 0.78%) in RNF186, a single-exon ring finger E3 ligase with strong colonic expression, protects against ulcerative colitis (overall P = 6.89x10-7, odds ratio (OR) = 0.30). We further demonstrate that the truncated protein is expressed, suggesting the protective mechanism may reside in the loss of an interaction or function via mislocalization or loss of an essential protein element.

Genetics

Association mapping of inflammatory bowel disease loci to single variant resolution

Inflammatory bowel disease (IBD) is a chronic gastrointestinal inflammatory disorder that affects millions worldwide. Genome-wide association studies (GWAS) have identified 200 IBD-associated loci, but few have been conclusively resolved to specific functional variants. Here we report fine-mapping of 94 IBD loci using high-density genotyping in 67,852 individuals. Of the 139 independent associations identified in these regions, 18 were pinpointed to a single causal variant with >95% certainty, and an additional 27 associations to a single variant with >50% certainty. These 45 variants are significantly enriched for protein-coding changes (n=13), direct disruption of transcription factor binding sites (n=3) and tissue specific epigenetic marks (n=10), with the latter category showing enrichment in specific immune cells among associations stronger in CD and gut mucosa among associations stronger in UC. The results of this study suggest that high-resolution, fine-mapping in large samples can convert many GWAS discoveries into statistically convincing causal variants, providing a powerful substrate for experimental elucidation of disease mechanisms.

Genetics