Genetic cause of rare high blood pressure syndrome discovered

Washington DC: A new study has discovered the genetic cause of a rare high blood pressure syndrome.

Professor Ute Scholl and a team of scientists from the United States and Australia have now identified a new hypertension disease gene. The study focused on a particular and very rare form of high blood pressure, known as familial hyper aldosteronism type II.

This inherited disease causes the adrenal gland to produce high level of aldosterone - a hormone that regulates the water and salt conservation in the kidneys. Excess of this hormone in the body shoots up the blood pressure.

According to the research, more than a billion people worldwide suffer from hypertension or high blood pressure. Such a condition, if prolonged, damages blood vessels, which can result in damage to the heart, the kidneys, and the brain.

Possible consequences may include heart attack, kidney failure and stroke. Besides obesity, salt consumption and alcohol intake, genetic factors play an important role in the development of hypertension.

In some rare cases, familial hypertension is caused by mutations within single genes. These genes play important roles in blood pressure determination. These mutations typically cause early-onset hypertension, even in young children and adolescents.

Type II of familial hyperaldosteronism was first described in an Australian family 25 years ago. The research team investigated this family along with other patients suffering from hyperaldosteronism in childhood and adolescence.

A total of eight families, including the large Australian family, showed mutations in a gene that had not previously been associated with blood pressure regulation. The CLCN2 gene carries information for building a channel in the cell membrane through which chloride ions can pass.

In specific cells of the adrenal gland, these chloride channels regulate membrane voltage and aldosterone production. Gene mutations in patients with familial hyperaldosteronism cause changes in the membrane voltage and result in the overproduction of aldosterone, which raises blood pressure.

The findings from this study have been published in the scientific journal Nature Genetics.