In the United States, babies receive their first blood test within the first two days of their lives. A prick to the newborn’s heel allows physicians to screen for potential congenital disorders, some of which can lead to severe disability or death. The blood is dropped on a card that is sent to state laboratories for analysis. Some results are stored in state databases and serve as an invaluable resource to public health researchers.
After researchers discovered genetic markers for certain disabilities in the 1960s, the American College of Medical Genetics identified a core panel of disorders that are detectable in a newborn’s blood sample. With the help of genetic markers, about 4,000 to 5,000 babies born every year are diagnosed with disorders, some of which were detected in baby’s first test.