In insulin-responsive tissues, adiponectin improves the sensitivity to this hormone.111,112 Hypoadiponectinemia, defined by plasma adiponectin levels lower than 4.0 μg/mL, was associated with decreased levels of circulating high-density lipoprotein, triglycerides and glucose, and increased risk of metabolic syndrome. The gene discussed is ADIPOQ; the disease is metabolic syndrome.