Printer Friendly

The heart and heredity.

Some of the complicated ways in which genes control cardiovascular function are beginning to come to light. According to a study from the University of Iowa in Iowa City, an inherited difference in blood flow patterns that may presage hypertension can be seen in childhood. And research at the Medical College of Virginia in Richmond indicates that there are two genetic factors controlling blood pressure and heart rate changes.

The Iowa study compared 13 children 12 to 18 years old whose parents had normal blood pressure with 12 children having a least one parent with hypertension, putting the children at higher risk of eventually developing the condition themselves. The children were put in a blood pressure-raising situation -- instructed to mentally subtract a two-digit number from a four-digit number in a specified period of time.

"We've found evidence of a different pattern in children genetically susceptible to hypertension," says Erling A. Anderson of Iowa. The difference was not in blood pressure or heart rate, which remained essentially the same in the two groups both before and after the stress, but in a significant increase in blood flow to the forearm in the children of hypertensives.

The Medical College of Virginia study suggests there may be two genetic compoents controlling heart rate and blood pressure. Researchers administered exercise tests to 83 sets of identical twins and 57 sets of nonidentical twins. Before and after work, they found a tighter correlation for blood pressure and heart rate values in the identical twins than in the nonidentical twins, as would be expected for a trait under genetic control. But in analyzing the rate of increase from rest to mental or physical work they found no significant similarities in either group of twins. This, they say, suggests there are different genetic factors controlling the relatively quiescent heart and the heart at work.
COPYRIGHT 1985 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1985, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Author:Silberner, Joanne
Publication:Science News
Date:Nov 23, 1985
Previous Article:Ever-changing shapes of nerve cells.
Next Article:The importance of having collateral.

Related Articles
The Hard Truth about Hearts.
Heart risks linked to infertility syndrome.
She seemed so healthy. (Executive Health Package).
Walker workout.
Citing Merck misconduct, jurors find for plaintiff in Vioxx retrial.
Surprise solo.
Cell of Cells: The Global Race to Capture and Control the Stem Cell.
Subject Matter.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters