Genetic Mutation Hikes Blood Pressure

Gene KCNJ5 prompts sodium retention and hypertension

(RxWiki News) A genetic mutation in small tumors of the adrenal glands appears to have interesting consequences. Researchers found that the gene mutation can cause sodium retention and subsequent hypertension.

About 40 percent of small adrenal tumors that negatively affect blood pressure were found to be tied to a mutation of gene KCNJ5.

"Reduce salt intake to benefit blood pressure."

William E. Rainey, PhD, study author and the scientific director of the Adrenal Center at Georgia Health Sciences University, said a combination of too much salt and an excessive amount of sodium-retaining hormone aldosterone leads to high blood pressure and tissue damage.

About a third of Americans suffer from high blood pressure. Adrenal causes are blamed in about 10 percent of those cases. Aldosterone excess is often suspect when individuals under the age of 40 develop high blood pressure for no other obvious reason.

During a pre-clinical study researchers placed the mutated gene into an adrenal cell, finding that prompted it and a series of other genes to immediately begin producing aldosterone. Investigators examined 47 human, benign adrenal gland tumors during the course of the research.

Under normal circumstances, KCNJ5 is believed to normalize levels of aldosterone, however, abnormal protein that the mutated gene produces alters the electrical status of the cells. This causes the cells to lose control and produce aldosterone all the time, Dr. Rainey said.

Investigators, who determined that the gene mutation was twice as likely to occur in women, are planning additional studies to pinpoint why women with adrenal tumors have more of the mutated gene.

Dr. Rainey suspects it may be related to estrogen.

The finding could help lead scientists toward new treatments for patients that don't respond to current hypertension medications.

The study was recently published in the Journal of Clinical Endocrinology and Metabolism.

Review Date: 
May 30, 2012