A gene that helps regulate heart rhythm has been linked with sudden infant death syndrome, (SIDS), and may help explain some of the deaths of apparently healthy babies in their sleep, doctors said yesterday. The gene, called SCN5A, helps control how heart cells use sodium to regulate their electrical rhythm, said Dr Michael Ackerman, of the Mayo Clinic in Minnesota.
"This is step one of many that could eventually prevent SIDS," Dr Ackerman said. "We're just starting to be able to identify those infants that may be at risk for SIDS and take steps to prevent the incidence of death." The gene is associated with long-QT syndrome, a heart irregularity that can cause sudden death.
"All we really know are the risk factors - sleep position, exposure to smoke, things like that. But we haven't really known what causes a healthy infant to die suddenly. Now we do know one of the causes is an electrical disturbance in the heart. In a way it the perfect culprit for SIDS because it would leave no clues at autopsy."
A screening test for the gene is not commercially available. But a campaign to encourage parents to put babies to sleep on their backs cut the rate of SIDS deaths by nearly half in the US and Britain.
"We clearly know the things every parent should do for babies," Dr Ackerman said.
"We encourage parents to place babies on their backs, we encourage pregnant women not to smoke and not to expose the baby to smoke, watch the amount of bedding in the crib so there is no chance of overheating or suffocating in the blankets, and to use a nice, firm mattress."