Evidence check: ADH1B in the context of fertility

The ADH1B gene variant (e.g., rs1229984) affects alcohol dehydrogenase activity and thus alcohol metabolism. Carriers of the faster variant (e.g., ADH1B*2) have a lower risk of alcohol dependence because even small amounts cause unpleasant side effects. A direct effect on fertility is not clearly established. However, altered alcohol metabolism may indirectly influence fertility: alcohol consumption is associated with reduced fertility in both women and men, and a genetically lower alcohol tolerance could lead to less consumption. The evidence is based on GWAS studies of alcohol consumption, not direct fertility studies. Effect sizes are small, and lifestyle factors dominate. The MyBody-X test does not provide a clinical risk assessment. Consult a physician or genetic counselor before drawing conclusions.