Researchers have discovered a gene variant that affects how the kidneys process salt and could help determine, which people are more likely to develop high blood pressure.

Yen-Pei Christy Chang, assistant professor of medicine, epidemiology and preventive medicine at the University of Maryland and study leader said that people with a common variant of the gene STK39 tend to have higher blood pressure levels and are more likely to develop hypertension later.

In the study the researchers analyzed the genes of 542 people who were members of the Old Order Amish community in Pennsylvania, who were ideal for such studies, because its members are relatively isolated and share a similar rural lifestyle and diet.

The researchers cross checked their findings with another group of Amish people as well as four other groups of white people in the United States as well as in Europe. They found about 20 % of the people studied carried either one or two copies of the gene and it is carried by about one of every five white Americans, said Chang.

The gene was responsible for producing a protein involved in regulating the way kidneys process salt in the body which was a major factor in determining blood pressure. Although this variant increases the blood pressure levels by about 3.3 points, the researchers felt it could lead to better treatment of hypertension which is a major risk factor for cardiovascular problems and stroke.

"What we hope is that by understanding STK39 we can use that information for personalized medicine, so 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 for side effects," Chang said.

Although the gene STK39 played a key role there could be other factors that influenced blood pressure such as being overweight, lack of exercise, smoking and too much salt in the diet said Chang. Currently several different types of medications are used to treat high blood pressure and their effectiveness varies depending on the person, and doctors can never know which is best for a particular patient.

Chang said, "We're now going back to the Amish again to study how these people react to different hypertension medications," she said. "This can help us find the best medication for hypertension in individual cases."

Dr. Richard S. Cooper, professor and chairman of preventive medicine at Loyola University's Stritch School of Medicine in suburban Chicago, and another member of the research team said it was not clear how much of a role STK39 played in blood pressure and how it could affect the treatment for the condition. "At this point, what is important is really a question of what it leads to next," Cooper said. "It is not a major determinant of blood pressure. We are trying to figure out in greater detail what the physiology of it is."

The study is published in the journal Proceedings of the National Academy of Sciences.