Loss-of-function CYP2A6 variant that abolishes nicotine metabolism, slowing clearance of nicotine, cotinine, coumarin, letrozole, tegafur, and efavirenz

Determines presence of alpha-actinin-3 protein in fast-twitch muscle fibers, influencing sprint/power vs endurance capacity

Intronic variant tagging the HNF4A P2 promoter risk haplotype; the T allele impairs glucose-stimulated insulin secretion — particularly in non-obese individuals — by reducing beta-cell-specific HNF4A isoform expression, and confers elevated diabetes risk with a notably strong effect under metabolic stress (OR 2.44 for post-transplant diabetes)

Missense variant in endothelial lipase that tags a regulatory haplotype associated with modestly higher HDL cholesterol through reduced LIPG expression

Intronic PON1 variant that modulates arylesterase activity of the HDL-bound antioxidant enzyme paraoxonase-1, influencing protection against LDL oxidation and atherosclerosis

Synonymous CFH variant in complete LD with rs1410996 that tags the complement-dysregulation haplotype driving age-related macular degeneration; G allele (risk) impairs complement regulation on retinal surfaces

Synonymous coding variant in ABCA1 that tags a regulatory element influencing transporter expression; the common G allele associates with the population-average HDL baseline, while the rare T allele associates with modestly higher HDL-cholesterol

Most common alpha-1 antitrypsin deficiency variant causing protein misfolding, lung disease, and liver disease

Macrophage-stimulating protein variant affecting innate immune response and IBD susceptibility

Affects anandamide levels through altered FAAH enzyme stability, influencing pain sensitivity, stress response, fear extinction, and mood regulation