Continuously updated · last reviewed Sep 5, 2026
Each page covers one condition properly: what it actually is and what it feels like, what causes it, how common it really is and in whom, and how it's diagnosed — followed by the specific variants with a replicated link to it, and, where the research supports it, how genetics can change the way a medicine behaves.
Written in two registers so one page serves both readers: plain language first, then a clinical detail section with the precise terminology, effect sizes and diagnostic thresholds. Every claim is sourced from freely-available published research and cited on the page, so you can check us — or hand the page to your doctor. 27 conditions so far, growing continuously, and free to reuse with attribution (CC BY 4.0).
A long-term inflammatory bowel disease in which the lining of the colon and rectum becomes inflamed and ulcerated, causing bloody diarrhoea, urgency and abdominal cramping that flare and remit over years.
Read more → NutritionalWhat vitamin D does, why medical bodies disagree on where "deficiency" begins, who is actually at risk, and why a common GC gene variant nudges measured vitamin D levels modestly without diagnosing deficiency on its own.
Read more → PharmacogenomicsWarfarin is an anticoagulant whose effective dose varies enormously between people. Common variation in VKORC1 — warfarin's direct target — plus CYP2C9 and CYP4F2 explains a large share of that variability.
Read more →Showing 3 of 27 · page 2 of 2