Heart Genes Could Help Explain SIDS

FRIDAY, May 18 (HealthDay News) -- Mayo Clinic researchers say they've spotted two cardiac genes that could be linked to sudden infant death syndrome (SIDS).

The findings increase the possibility that genetic defects of the heart may cause up to 15 percent of SIDS cases.

The team examined tissue from 135 infants, average age 3 months, who died of SIDS, and found evidence to implicate caveolin-3 (CAV3) and cardiac ryanodine receptor (RyR2) as SIDS-susceptibility genes. Of the 135 infants in the study, all by two had mutations in either CAV3 or RyR2.

SIDS -- the sudden, unexplained death of an infant under 1 year old -- is estimated to cause 2,500 infant deaths each year.

"Combined with our previous discoveries, we now estimate that defects in genes that provide the blueprints for the critical controllers of the heart's electrical system might have played a key role in more than 300 of those tragedies," principal investigator Dr. Michael J. Ackerman, director of Mayo Clinic's Long QT Syndrome Clinic and Sudden Death Genomics Laboratory in Rochester, Minn., said in a prepared statement.

"We are continuing to expose the causes of SIDS. So far, we have now added six genes to the SIDS most-wanted list," Ackerman said.

The findings were to be presented today at the Heart Rhythm Society's annual scientific sessions, in Boston.

"Although so much of SIDS remains unexplained, these findings that point to the heart for 10 percent to 15 percent of SIDS provide one place to search for a possible explanation," Ackerman said.

"For families that have lost an infant to SIDS, it would be reasonable for parents to talk with their physician to make sure there is no family history of other unexplained deaths, unexplained fainting episodes, unexplained seizures that might provide clues and prevent more deaths," Ackerman added.