FRIDAY, Jan. 19 (HealthDay News) -- Almost 10 percent of babies who die of sudden infant death syndrome (SIDS) have gene variations or mutations associated with potentially deadly heart rhythms (arrhythmias), according to two new studies.

Publishing their work online this week in the journal Circulation, researchers in Italy, Norway and the United States looked at genes from 201 SIDS victims and found that 9.5 percent of them had mutations in genes associated with inherited forms of arrhythmia.

Among the mutated genes identified by the researchers was a gene (SCN5A) that encodes the cardiac sodium channel -- a protein that regulates the electrical properties of heart cells.

The same researchers also concluded that mutations in heart potassium channels also contribute to SIDS.

The findings raise the possibility of identifying infants who have these genetic mutations.

"We are not recommending that a population-wide genetic screening be done, but there may be simpler, cost-effective measures that should be investigated further, perhaps performing ECG (electrocardiogram) screening of infants, although this idea is controversial," Dr. Alfred L. George Jr., professor of medicine and director of the division of genetic medicine at Vanderbilt University Medical Center in Nashville, Tenn., said in a prepared statement.

George, who was senior author of one of the studies, noted that inherited arrhythmias can be managed with medications or implantable cardiac devices.

"There's potentially an infant death every other day in the U.S. due to this problem. Exactly how best to identify this risk and prevent arrhythmia-related death during infancy needs to be determined," George said.

Each year in the United States, about 2,200 infant deaths are attributed to SIDS, according to the Centers for Disease Control and Prevention.

More information

The Nemours Foundation has more about SIDS.