Chromosome X Evidence Atlas

Mapping the Signals
Most Studies Leave Behind

Chromosome X carries hundreds of genes that influence traits from blood chemistry to cognition. Many GWAS summary-stat resources still under-analyze or omit it. chrXatlas maps where the signals are, which traits they touch, and which genes are nearby or show follow-up eQTL evidence.

Explore the Atlas
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Curated Traits
ChrX Loci Mapped
eQTL Support Rate
Biological Domains

Current data build: —

Curated Panels

Three focused lenses on chromosome X signal. Each panel is curated for a specific research question, with ranked traits, mapped loci, and eQTL follow-up reported as lookup-hits or stricter support.

Why Chromosome X

The Blind Spot

Chromosome X is routinely dropped from genome-wide association studies. Different copy numbers in males (XY) and females (XX) create analytical complications that most pipelines simply bypass. The result: an entire chromosome — encoding ~800 protein-coding genes — remains systematically under-explored in the era of biobank-scale genetics.

What We Built

chrXatlas is a ranked, evidence-scored discovery atlas of chromosome X associations built from Pan-UK Biobank summary statistics. For each trait, we identify genome-wide significant loci on chrX, map candidate genes by proximity, and add targeted follow-up from prioritized eQTL datasets.

Why It Matters

The X chromosome influences immune function, metabolism, brain development, and dozens of other processes. By making these associations visible and comparable across traits, chrXatlas provides a structured starting point for researchers who want to understand what chromosome X contributes — and what has been missed.

Atlas Results

Signal composition, top-ranked traits, and panel comparisons from the current build.

Panel Comparison

Domain Composition — Broad Atlas

Loci distribution across biological domains in the featured all-purpose panel.

Top-Ranked Traits

Highest evidence-scored traits from the Broad Atlas panel.

Discovery Pool

A broader reservoir of 150 traits from the Pan-UKB max independent set. Not curated to the same standard as the featured panels, but kept as a source for future exploration and panel building. Expand the drawers below to inspect the full tested set and the traits without strict current eQTL support.

Reading the Atlas

A plain-English guide to the key concepts behind chrXatlas results.

What is a chrX signal?

A "signal" in this atlas is a genome-wide significant association (p < 5 × 10−8) located on chromosome X. We scan Pan-UK Biobank summary statistics for each trait, identify significant variants on chrX, and merge nearby signals into distinct loci using distance-based clustering.

What do the eQTL labels mean?

An eQTL lookup-hit means the rsID-based follow-up returned associations in the prioritized datasets. eQTL-supported is narrower: at least one candidate gene at a chrX locus passed the current strict support rule after aggregation across the queried datasets. Neither label is a tissue-relevance model or a causal claim.

Coverage grades

Coverage grades reflect upstream GWAS data quality, not eQTL follow-up completeness. Grade A means the trait is in the Pan-UKB max independent set, passes QC in 2+ populations, and has a large high-quality cohort (≥50K). Grade B indicates partial coverage — in the independent set with ≥10K, or multi-population QC. Grade U means the trait does not meet these thresholds.

What the atlas is not

This atlas does not measure "how much of a trait is caused by chromosome X." It does not perform sex-stratified analysis or model dosage compensation explicitly. It uses sex-combined GWAS summary statistics. The atlas identifies where on chromosome X we see associations and adds rule-based gene mapping plus targeted eQTL follow-up.

About chrXatlas

Built from publicly available summary statistics from the Pan-UK Biobank project, with eQTL follow-up data from the eQTL Catalogue. Gene annotations use Ensembl GRCh37 coordinates.

This project is independent research. It is not affiliated with or endorsed by UK Biobank, the Pan-UKB team, or any of the data providers.