Evidence check: VKORC1 in the context of Schlaf

VKORC1 encodes vitamin K epoxide reductase and is well-established in pharmacogenetics for warfarin sensitivity. However, there is no robust scientific evidence linking VKORC1 variants to sleep quality, insomnia, or circadian regulation. Any claims connecting VKORC1 to sleep are speculative and based on weak mechanistic hypotheses (e.g., vitamin K's role in brain sphingolipids). No human observational or interventional studies support a direct effect. Consumer DNA reports that include VKORC1 in a sleep context are likely overextending the evidence. For sleep genetics, better-supported markers include PER3, CLOCK, and ADRB1. Do not change sleep habits or supplement based on VKORC1 results.