ISTOCK, BIT245
Before newborn screening was introduced in the 1960s, phenylketonuria, a rare, inherited condition in which the body is unable to properly metabolize the amino acid phenylalanine, was a devastating disease. Without treatment, the buildup of phenylalanine, a key component of proteins we eat, had toxic effects on neural and cognitive development. As a result, patients often developed severe mental disabilities as well as seizures, behavioral problems, and psychiatric disorders.
The ability to identify patients with phenylketonuria (PKU) at birth—and to treat them with low-phenylalanine diets—has resulted in a “much better outcome for individuals with PKU than before,” says Francjan van Spronsen, a pediatrician specializing in inherited metabolic diseases at the University of Groningen in the Netherlands. “Acknowledging that, we have to consider that the dietary ...