Myths vs facts: VKORC1 and blood sugar

The claim that VKORC1 variants directly affect blood sugar is not supported by robust evidence. VKORC1 encodes vitamin K epoxide reductase, a key enzyme in the vitamin K cycle, primarily relevant for blood coagulation and bone metabolism. Some research has explored links between vitamin K status and insulin resistance, but direct associations between VKORC1 polymorphisms and fasting glucose or HbA1c are weak and inconsistent. Most findings come from exploratory GWAS with small effect sizes and lack replication. VKORC1 is mainly known for its pharmacogenetic role in warfarin dosing, not for glucose regulation. Consumer DNA tests marketing VKORC1 as a 'blood sugar gene' overstate its clinical utility. Fact: Blood sugar is predominantly influenced by insulin secretion, insulin sensitivity, diet, and physical activity. Genetic testing for VKORC1 offers no actionable insight for glycemic control. Evidence-based approaches should focus on established biomarkers and lifestyle interventions.