In the search for the inheritable determinants of EH phenotype in humans, the gene encoding for the β2-adrenergic receptor (ADRB2) has been investigated worldwide, since in hypertension vascular responses to ADRB2 stimulation are impaired [3], [4] and the ADRB2 gene polymorphisms appear to affect vasodilation [5], [6]. Here, ADRB2 is linked to Hypertension.