Qtlizer

The software tool "Qtlizer" facilitates the annotation of genetic variants in human genomes by quantitatively linking them to gene expression and protein abundance changes through an integrated database of published quantitative trait loci (QTLs). Addressing challenges posed by diverse QTL databases and the absence of batch annotation features in genome-wide association studies (GWAS), Qtlizer allows comprehensive annotation of GWAS results. Noteworthy features include consideration of variants in linkage disequilibrium and a reverse search option using gene names.

The tool challenges the commonly used cis-distance limit of 1,000,000 base pairs by analyzing base pair distances between the most significant expression QTLs (eQTLs) and their associated genes, suggesting potential inaccuracies in eQTL detection. Additionally, Qtlizer ranks genes based on the consistency of their most significant eQTL signals across tissue-specific studies, revealing enrichment patterns such as a strong association with housekeeping genes.