Research program
Evaluating Polygenic Risk Scores at Scale
How well does a polygenic risk score work outside the study where it was developed?
We compare published scores in large biobanks and release the results, methods, and score files so that other researchers can inspect the evaluations.
Why external evaluation matters
Polygenic risk scores often perform best in the data used to develop them. Testing them in another population or health system, or with a different phenotype definition, shows which results replicate, which differ across datasets, and which need further study.
What we evaluate
Start with the published score
Each evaluation records the score definition, trait, and source study so readers can understand the comparison.
Test it in independent data
PRSweb reports evaluations from the Michigan Genomics Initiative and UK Biobank side by side.
Report more than one metric
Calibration, discrimination, and phenome-wide associations answer different questions about a score's performance.
Keep each release tied to its paper
Each archived PRSweb release includes the score files, mappings, results, and citation for its published analysis.
Selected work
These papers compare disease and exposure scores across biobanks, assess performance across ancestry groups, and test whether scores distinguish clinically important disease. The portal cards link to all three PRSweb releases.
Current work
Projects and collaborations
Public research resource
Current collection with archived releasesPRSweb Research Portals
PRSweb provides polygenic risk score evaluations, phenome-wide association results, and downloadable score files.
Related resources
Tools & data
Polygenic risk resource
Public collectionPRSweb Research Portals
Compare published polygenic risk scores evaluated in the Michigan Genomics Initiative (MGI) and UK Biobank, and explore phenome-wide associations and downloadable files.
Polygenic risk archive
Archived releaseCancer PRSweb
The archived June 2020 release reports evaluations of cancer polygenic risk scores in the Michigan Genomics Initiative (MGI) and UK Biobank.
Polygenic risk archive
Archived releaseExPRSweb
The archived November 2021 release reports evaluations of polygenic risk scores for common health-related exposures.
Polygenic risk archive
Archived releaseSkin Cancer PRSweb
The original June 2019 release evaluates 20 polygenic risk scores for melanoma, basal cell carcinoma, squamous cell carcinoma, and overall skin cancer.
PheWAS software
PublicphewasFlow
An R package for reproducible phenome-wide association studies in both directions, with local and cluster workflows, multiple-testing correction, and Manhattan and volcano plots.
Publications
Selected papers
Cancer PRSweb: An Online Repository with Polygenic Risk Scores for Major Cancer Traits and Their Evaluation in Two Independent Biobanks
American Journal of Human Genetics
Why it matters: Cancer PRSweb evaluated published cancer scores with the same methods in two independent biobanks. The side-by-side results show how performance differs by source GWAS, score-building method, phenotype definition, and cohort.
ExPRSweb: An online repository with polygenic risk scores for common health-related exposures
American Journal of Human Genetics
Why it matters: Smoking, body mass, lipid levels, and other exposures that shape disease risk are absent or unevenly recorded in clinical data. ExPRSweb evaluates whether genetic predisposition to these exposures adds information to phenome-wide analyses and prediction. These genetic scores can complement measured exposure data, but they do not replace it.
On cross-ancestry cancer polygenic risk scores
PLOS Genetics
Why it matters: Breast and prostate cancer scores built from genome-wide association studies in people of European ancestry performed differently across ancestry groups in UK Biobank, so the same absolute cutoff did not apply to every group. Within each group, rankings still separated people by risk. The paper shows the difference between a score that ranks risk within a group and one that can be interpreted the same way across groups.
Assessing the Clinical Utility of Published Prostate Cancer Polygenic Risk Scores in a Large Biobank Data Set
European Urology Oncology
Why it matters: Researchers tested 16 published prostate cancer scores in the Michigan Genomics Initiative (MGI) and used detailed biopsy data to evaluate their clinical utility. Even the best-performing score separated cases from controls only modestly, and none distinguished aggressive from indolent disease. Predicting a diagnosis is not the same as identifying the cancers that most need treatment.
Updates
News and talks
· Video
MGI 2024: Lars Fritsche
In this U-M symposium talk, Lars Fritsche reviews a decade of EHR-linked genetics research, including PheWeb and PRSweb.
· Research resource
Democratizing genetic data for cancer research
Michigan IT covered the launch of Cancer PRSweb and its public comparisons of polygenic risk scores.