Kim Johnson reportingIt's one of the most frightening things a new parent has to worry about -- Sudden Infant Death Syndrome.
Now, medical researchers in Arizona just might have uncovered a genetic connection, and a small breakthrough, in the understanding of SIDS.
Researchers at the Translational Genomics Institute in Phoenix studied Amish families in Pennsylvania.
Over two generations, nine families from one Amish community lost 21 infants to SIDS.
Researchers found all the babies who inheritied two copies of a defective gene died before their first birthday.
They've identified the gene as TSPYL, and they say it plays a role in the brain's ability to control breathing and heart rate, two functions that go awry in SIDS.
The head of Utah's Children Adolescent and School Health Program, or CASH, tracks SIDS cases, and says the development is exciting.
Al Romeo/ Manager, CASH: "The SIDS diagnosis is one of exclusion. Medical examiners look at everything else, and if they can't find anything, then it's determined to be a SIDS death. So this is very promising in that we don't understand everything, and we're hopeful we will understand it better in the future."
It's estimated that half the Amish population carries the defective gene.
Researchers aren't sure what percentage of the rest of the American population may be carriers.
One Salt Lake geneticist says it's likely to be small.
Dr. Alan Rope/ Medical Geneticist: "To say this is applicable to SIDS in the country at large is not only unlikely, but would also be a reckless statement, because we just don't know. It's possible that this accounts for all SIDS, but that's really a real stretch."
Some scientists say the discovery of the defective gene should explain some cases of SIDS, and could lead to blood tests to identify carriers, even someday treatments.
But until scientists uncover more pieces of the SIDS puzzle, the best advice for parents is to provide an environmnet free of cigarette smoke, to put baby to sleep on her back, and on a firm mattress, and finally to remove stuffed animals or heavy blankets that could interfere with the baby's air supply.
Since a public health campaign urging parents to do things like put their babies to sleep on their backs, SIDS deaths in Utah have decreased from an average of 50 a year to 12 in 2002, the last year measured.