Starting point The largest and most recent searches of the genome (Mark Caulfield and colleagues, Lancet 2003; 361: 2118–23; Michael Province and colleagues, Am J Hypertens 2003; 16: 144–47) have found limited evidence of genes that determine hypertension, and even less evidence for the existence of causative DNA variants (alleles) within these genes. Previous genomic studies did not reach a consensus on the likely location of bloodpressure genes. The difficulty in identifying genetic causes for common conditions might be because the causative alleles are numerous, with small individual impact, and are distributed unevenly between populations.

Where next? Without comprehensive and reliable description of the alleles associated with hypertension, using genetics for diagnosis remains tenuous. However, the discovery of a single allele proven to be associated with control of blood pressure could lead to the discovery of relevant and novel physiological targets for the prevention and treatment of hypertension.