An estimated 20 per cent of Caucasians carry a gene variant that could raise the risk of developing high blood pressure or hypertension, as it is also called.
US scientists at the University of Maryland, School of Medicine analysed the DNA of 542 members of the Old Order Amish community in Lancaster County, Pennsylvania and discovered that those carrying the STK39 gene variant had raised blood pressure, compared to those carrying other versions of the gene. One in four people living in western countries are thought to have high blood pressure, which can lead to an increased risk of cardiovascular disease, stroke, end stage kidney disease and even death. Better ways of treating hypertension patients are constantly being sought.
The results of the study, published in the Proceedings of the National Academy of Sciences, were reproduced when members of another Amish community, as well as four other groups of Caucasian volunteers had their DNA analysed. After looking for genes with a possible link to increased hypertension, STK39 emerged as a likely candidate. Located on chromosome 2, the STK39 gene produces a protein which helps to regulate how the kidneys process salt, which is a key determining factor in blood pressure.
Dr Yen-Pei Christy Chang, one of the researchers in the study believes that the discovery of this genetic variation will help develop a more 'personalised' treatment programme for individuals with increased hypertension. 'What we hope is that by understanding STK39 we can use that information for personalised medicine, so that we can actually predict which hypertensive patients should be on what class of medication, and know that they will respond well and have minimal risk of side effects' Chang said.
Whilst the gene variant looks to be a strong indicator for certain individuals, Dr Chang added that 'hypertension is a very complex condition, with numerous other genetic, environmental and lifestyle factors involved...finding the best treatment among all possible ones is still a very "try and see" process'. Mike Rich, executive director of the Blood Pressure Association described the results as 'interesting', saying that 'there are already indicators which can help us determine who is more likely to develop the condition, such as a family history of hypertension, heart disease, stroke and poor diet and lack of exercise'.
The Amish were thought to be an ideal group for the US study because they are a genetically homogeneous people whose ancestors can be traced to a small group arriving in the US from Europe in the 1700s. As a result of the study, some participants began treatment for their previously undiagnosed hypertension.