For the first time, we have techniques available that may enable us to determine cause and effect in common cardiovascular diseases. The observations presented herein require cautious interpretation until replicated. There are currently several large programs under way that seek to establish substantial family resources for investigation of the genetic basis of hypertension. When interpreting the results of genome screens, it will be necessary to consider that we may link genetic loci for coexistent features such as dyslipidemia and insulin resistance to hypertension. Therefore, careful phenotypic data will be necessary to dissect out the causes of hypertension.