Genetic variants that affect proteins involved in making aldosterone and cortisol, hormones that regulate the circulatory system, have been identified as risk factors for hypertension, or high blood pressure.
Hypertension has long been understood as a disease caused by both genetic and environmental factors. However, as Professor John Connell, from the University of Dundee, who led the study, says, 'it has proved very difficult to identify genetic causes of hypertension. But this research shows that a gene variation that is present in around 40 percent of the population is a significant factor'.
The discovery may have more immediate implications for treatment than is often the case in genetic research. 'Drugs targeting aldosterone are already used in the treatment of hypertension, so this study emphasises that these should be more widely used', says Professor Connell.
'We know that the effects of aldosterone are amplified by a high salt diet, so this could give an important clue to an interaction between a common genetic variation and the environment', he added.
The study, published in the journal Hypertension, used data collected from 5,900 patients in the UK and Scandinavia. The results lend weight to a theoretical model which previously suggested that carriers of the genetic variants would have a higher risk of developing hypertension.
'One of the extremely satisfying aspects of this research has been that we have been able to take that theory all the way through to firm findings that show how the gene variation leads to altered function', said Professor Eleanor Davies, lead investigator from the University of Glasgow.
According to the Health Survey for England 2010 nearly a third of the general population have hypertension. Although high blood pressure can often be controlled with medication it remains a major risk factor for heart attacks, stroke and heart failure.
Professor Connell said that his team were now looking 'to carry out further research, particularly with regard to the importance of genetically determined variation in aldosterone in other forms of cardiovascular disease'.