PheWAS
PheWAS, or Phenome-Wide Association Study, is a method used in genetic epidemiology to investigate associations between genetic variants and a broad range of phenotypes simultaneously. The concept was introduced to complement Genome-Wide Association Studies (GWAS), which examine many genetic loci for a single phenotype, by instead scanning many phenotypes for potentially meaningful associations with a single genetic marker or set of markers.
The approach typically relies on large, routinely collected health data, such as electronic health record (EHR)
Applications of PheWAS include mapping the phenotypic effects of risk alleles, uncovering pleiotropic relationships where one
Challenges include phenotype misclassification, population stratification, and the computational burden of testing millions of variant–phenotype pairs.