Final enzyme in melatonin synthesis; promoter variant reduces ASMT expression and lowers melatonin production, affecting sleep onset and circadian rhythm

Promoter variant that reduces APOA2 expression by 30%; GG homozygotes consuming more than 22g saturated fat daily have 84% higher obesity odds than AA/AG carriers

Intronic variant in SIRT1 affecting NAD-dependent deacetylase expression and oxidative stress protection

Intronic RAD50 variant in the Th2 locus control region (RHS7); T allele alters SMAD3 and SP1 transcription factor binding, shifts DNA methylation at the IL13 promoter in cord blood, and is associated with elevated total IgE levels and atopic disease risk.

Tag SNP for HLA-DRB5*01:01 on the DR15 susceptibility haplotype, physically near HLA-DRB5 in the MHC region and in near-complete LD with rs3135388; the DRB5*01:01 allele contributes independently to multiple sclerosis and narcolepsy risk by presenting myelin and viral peptides to autoreactive CD4+ T cells

Tag SNP proxy for GSTM1 gene deletion status — the most common pharmacogenomic variant worldwide, eliminating a Phase II detoxification enzyme that conjugates glutathione to environmental carcinogens

Near-complete loss-of-function CYP2B6 variant causing severely impaired metabolism of efavirenz, bupropion, methadone, and other CYP2B6 substrates

Common intronic variant near glucokinase that raises fasting glucose by impairing the pancreatic glucose-sensing threshold; each A allele adds ~0.062 mmol/L to fasting glucose and modestly reduces beta-cell function

Missense variant in glyoxalase 1 reducing enzyme activity, allowing methylglyoxal to accumulate — a GABA-A receptor modulator that influences anxiety and sleep quality

Intergenic variant near the SFRP5 adipokine locus; the A allele is strongly enriched in African ancestry (~19% MAF) and absent in East Asian populations, tagging a regulatory region that may influence SFRP5 expression — the anti-inflammatory adipokine that suppresses pro-inflammatory Wnt5a signaling in adipose tissue