GWAS (Genome-wide association study)

A genome-wide association study (GWAS) is a hypothesis-free scan of the common variants in your DNA (SNPs, usually present in over 1 to 5% of people) across the whole genome. It looks for spots statistically linked to a trait or disease. To avoid false hits from testing about a million variants, it uses a strict significance bar (p < 5×10⁻⁸). GWAS runs on the 'common-disease, common-variant' idea and suits polygenic traits. Most variants it finds have small individual effects (odds ratios of 1.05 to 1.3). So it needs very large samples (tens to hundreds of thousands of people) to detect them reliably. For longevity, GWAS hits are relatively sparse. The APOE locus (especially ε2 protection and ε4 risk) is by far the strongest and most replicated hit for exceptional longevity. Other candidates (FOXO3, TOMM40/APOC1, CDKN2B-AS1) have some support but do not replicate everywhere. The thin yield likely reflects longevity's heterogeneous, polygenic, and late-acting genetic makeup.

Last reviewed: June 22, 2026

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