A blood test developed in the 1960s to screen for PKU, or phenylketonuria, led to infant testing for a variety of diseases and disorders.

Since 1965, Maine’s Newborn Screening Program has required babies here be tested for nine disorders that, if not caught, can lead to blindness, seizures, severe mental retardation and early death. Refusal is allowed only for religious reasons.

Ellie Mulcahy, program director for genetics, said of the 13,000 babies born in Maine each year, more than 99 percent are tested for those nine, and more than 99 percent also opt to check for 19 additional disorders. It’s all done with one heel prick’s worth of blood taken before the baby leaves the hospital.

In the last two years, Mulcahy said, 50 babies have tested positive for any of those 28 disorders. Roughly three had a family history, the rest did not.

In the case of PKU, Lori Rice and her husband didn’t know they were both carriers of the gene until the birth of their third child 7 years ago. They had a one-in-four chance of having a PKU child. Their two other children – boys 10 and 17 – don’t have the disorder.