Using techniques normally applied to the study of space, researchers report they have found an abnormality in the electrical activity of the heart that may cause half of all crib deaths.
Stressing that the research was preliminary, the researchers said the findings could eventually offer the first way to screen babies to identify those at risk for crib death.
"That's very exciting," said Dr. Marie Valdes-Dapena, chairman of the board of the National SIDS Foundation. "If you say you can explain half (of the deaths) that would be earthshaking in my view."
Crib death, which is also known as sudden infant death syndrome or SIDS, kills an estimated 7,000 babies each year in the United States. Infants with SIDS suddenly die, usually in the first four months of life.
"This work is only a clue to a possible mechanism," said Dr. Daniel C. Shannon, who headed the new research at Massachusetts General Hospital.