The investigators found that hcmv-miR-UL112, a human cytomegalovirus (HCMV)-encoded miRNA, was highly expressed in the hypertensive patients. Among the top miRNA target predictions, the investigators demonstrate that IRF-1 is a direct target gene of hcmv-miR-UL112, along with MICB that has been previously reported. Both IRF-1 and MICB play critical roles in immuno/inflammatory and anti-infection response. Thus, the investigators speculated that IRF-1 and MICB repression by hcmv-miR-UL112 could be considered a unifying mechanism that evades the host response at several levels: antiviral, inflammatory, and immune. In addition, there is an increasing evidence that IRF-1 may be important in apoptosis, angiogenesis, neointima formation and the pathogenesis of vascular diseases. IRF-1 can up-regulate angiotensin II type 2 receptor (AGTR2) that exerts antiproliferative and proapoptotic actions and affects regulation of blood pressure. It has been reported that the targeted disruption of the mouse AGTR2 gene resulted in a significant increase in blood pressure and increased sensitivity to angiotensin II. The nitric oxide synthase expression and NO synthesis in macrophages and distinct cardiomyocytes are induced and controlled by IRF-1 in response to inflammation, important steps in vascular biology that may improve endothelial function and inhibit smooth muscle cell migration, and a key pathophysiological event in hypertension. Collectively, these reports support a strong relationship between IRF-1 regulation and hypertension, indicating a potential role of hcmv-miR-UL112 and HCMV infection in the pathogenesis of hypertension.Thus, the investigators want to investigate the potential link between HCMV infection and essential hypertension.