Ally Zwahlen and her husband Steve are eager to start a family. They are both in good health. But they want to assess the risks: are they in danger of having children with a rare, inherited disease or some sort of devastating illness?
A new form of screening, called the Counsyl Universal Genetic Test, could give them the answers they need.
"I'm confident that it's going to alleviate a lot of uncertainties, and provide peace of mind," Ally, who is 32 and lives in Danville, Calif., told ABC News.
Some doctors are gushing about the new test.
"I tell all my friends about it," said Dr. Aimee Eyvazzadeh of John Muir Health Systems near San Francisco. "You know, my girlfriends who are getting married right now and who are planning a pregnancy? I tell them, 'Before you get pregnant, do this test.'"
Unlike traditional genetic tests, which require a blood sample to help find one specific disease, the new test uses a little saliva to look for genetic markers linked to 109 inherited diseased ranging from cystic fibrosis and Pompe disease to sickle cell disease and Tay-Sachs.
"We are looking for mutations that parents unknowingly carry. They would have no symptoms," said Ramji Srinivasan, CEO of Counsyl, the company making the new test. "Before today, it had never been easy, convenient and reliable to get a pre-pregnancy test at home," he said. "This will dramatically reduce the incidence of diseases that are passed from parent to child."
For $350, Counsyl says it will screen the samples at its lab in Redwood City, Calif., looking for more than 400 genetic mutations. The company says the results are available in less than a week.
If both husband and wife test positive for the same disease, there are steps they can take to protect their future children. Couples could go through in vitro fertilization, for example; doctors could check each resulting embryo and implant only those that appear free of disease.
Many geneticists we contacted, though excited about the new test, do urge caution.
"This new genetic test is an important first step," says Dr. Priya Kishnani, a geneticist at Duke University Medical Center told ABC News. "But the jury is still out on whether it can deliver everything it promises; whether it's as thorough and definitive as the marketing suggests."
Dr. Kishnani says some parents may be left with a false sense of security. There are many disease-causing mutations that the test does not cover. And some of the mutations targeted in the test are so hard to interpret that some couples could go through the expense and anxiety of in vitro fertilization for nothing.
What is clear is that more such tests will soon be on the market. The appeal can be so great: The prospect of sparing families the heartache of a new baby with a preventable disease.