LANSING, Mich. (Michigan News Source) – A judge found key parts of Michigan’s newborn blood-testing program unconstitutional in a challenge from four parents who raised concerns about how leftover samples are used long after screening for rare diseases.

This week’s decision is likely to have an impact on how the state of Michigan maintains millions of dried blood spots and makes them available for outside research.

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Research with newborn blood spots occurs in other states, too.

“Michigan undoubtedly has some level of interest in detecting rare blood diseases in its infant population,” U.S. District Judge Thomas Ludington said. “Defendants’ post-testing conduct is not necessary to effectuate that interest because ‘the health of the child is no longer at stake.’”

At the state’s direction, Michigan hospitals routinely prick the heels of newborns to draw blood to check for more than 50 diseases, a longstanding practice across the U.S.

Leftover blood spots are sent to the Michigan Neonatal Biobank in Detroit for safekeeping. Scientists can pay a fee to use them for various research projects.

The health department has defended the program. It says no spots are stored for research unless parents give permission. Spots also can be destroyed upon request.