COLSTATS: an interactive web platform for systematic colocalization of GWAS and QTL summary statistics

Abstract

Colocalization of GWAS with QTL data is pivotal for identifying shared genetic determinants of molecular traits and diseases yet remains hindered by fragmented data sources and technical barriers. COLSTATS addresses this gap by offering a web-based Shiny platform that integrates 1,648,851 harmonized summary statistic datasets from key resources (GWAS Catalog, UK Biobank, GTEx, BluePrint, eQTLGen, and immune-phenotype studies), all formatted as VCFs aligned to hg38 with uniform chr_pos_ref_alt variant identifiers. Users can interactively select two traits, specify a genomic region or gene, define priors, and execute colocalization via coloc.abf, with results displayed in tabular and graphical form, downloadable as PDF, CSV, or PNG. The system includes result caching, history tracking, and an intuitive interface for streamlined exploration.COLSTATS is freely accessible at https://colstats.irgb.cnr.it. This resource empowers researchers, including non-bioinformaticians, to perform transparent and reproducible colocalization analyses efficiently.