Intronic variant in the intestinal and renal vitamin C transporter gene (SVCT1) that independently predicts circulating plasma vitamin C levels, with the A allele associated with reduced ascorbate concentrations

Intronic regulatory variant in TSHR intron 1 that is the primary PLZF repressor-binding site in the open chromatin region controlling thymic TSHR expression; the T allele allows stronger PLZF binding, reduces intrathymic TSHR levels, impairs central immune tolerance to thyroid antigens, and confers susceptibility to Graves' disease

Missense variant in ZIP4 zinc transporter causing total loss of intestinal zinc absorption when homozygous; responsible for classical acrodermatitis enteropathica

Near-gene variant at the IL12B locus associated with psoriasis risk through altered expression of the p40 subunit shared by IL-12 and IL-23 cytokines

Pathogenic missense in antithrombin III; the A allele causes type II heparin-binding-site (HBS) antithrombin deficiency with heterozygotes carrying 3-5x VTE risk and homozygotes facing severe, often childhood-onset thrombophilia

Ashkenazi Jewish founder missense mutation in coagulation factor XI causing impaired FXI dimerization; homozygotes develop hemophilia C (severe FXI deficiency) with post-surgical and trauma-related bleeding, while heterozygotes have partial deficiency with variable bleeding risk; the most prevalent FXI deficiency allele in Ashkenazi Jewish populations

Regulatory variant in IRF4 enhancer affecting melanocyte pigmentation, sun sensitivity, freckling, and melanoma susceptibility

Intronic LIPC variant in intron 1 associated with low HDL risk, predominantly in women; the C allele is the risk allele for reduced HDL-cholesterol levels

An intronic variant in HELQ (helicase, POLQ-like) on chromosome 4q21.23; the A allele is associated with delayed age at natural menopause (+0.238 years/allele, p=6×10⁻¹⁷²), reflecting HELQ's role in maintaining the oocyte DNA-repair capacity that preserves ovarian reserve across the reproductive lifespan

Influences vitamin D synthesis by regulating how much 7-dehydrocholesterol is available for conversion to vitamin D3 in the skin