WASHINGTON – A critical safety net for babies – that heel prick of blood taken from every newborn in the U.S. – is facing an ethics attack.

J. SCOTT APPLEWHITE/The Associated Press

Heel prick samples from newborns, such as this 1-day-old boy in Washington, D.C., are tested for at least 29 diseases.

After those tiny blood spots are tested for devastating diseases, they're stored for years in some states. Scientists consider the leftover samples a treasure, both to improve newborn screening and to study bigger questions, such as which genes trigger childhood cancers.

But seldom are parents asked to consent to such research – most probably don't know it occurs – raising privacy concerns that are shaking up one of public health's most successful programs.

Texas is poised to throw away blood samples from more than 5 million babies to settle a lawsuit from parents angry at what they call secret DNA warehousing. A judge recently dismissed a similar lawsuit in Minnesota.

Michigan just moved 4 million leftover blood spots into a new BioTrust for Health, planning a public education campaign about the research potential and how families can opt out.

Advisers to the U.S. government hope to have national recommendations in two months on how to ensure that all babies get their newborn tests while allowing parents more say in what happens next.

"It's a critical thing that we take action," says advisory board member Sharon Terry of the nonprofit Genetic Alliance. She says distrust over the leftover blood spots threatens public confidence in newborn screening itself.

Every baby is supposed to be tested for at least 29 rare genetic diseases in hopes of catching the fraction who need early treatment to help avoid brain damage or death.

Because newborn screening is mandatory, only a handful of states provide much upfront parent education. Leftover spots are mainly used for double-checking that newborn tests are accurate.

But as scientists sought to use the leftovers for broader research, suddenly the informing of parents – especially about long-stored spots – became an issue. While blood spots are stripped of identifying information before being handed over to scientists, people generally need to consent to participate in research.

"My kid is not a lab rat. You have to ask before you can use him in an experiment before you can use his blood, his tissues, his DNA, whatever," says Andrea Beleno, one of the Texas parents who sued.

To scientists who pore through dusty warehouses in search of blood samples stored by health department ID codes – not the babies' names – privacy concerns are exaggerated.

Still, researcher Jennifer Puck of the University of California, San Francisco, understands parents' concerns.

"DNA is your personal signature, and it uniquely identifies us," Puck says. "We all have to become more careful and more specific in terms of what we're going to do with the blood spots."

Lauran Neergaard,

The Associated Press