The Future of Newborn Genomic Screening

GS provides exciting opportunities to rapidly identify a diagnosis in critically ill newborns and children with rare genetic conditions. But there are good reasons to remain cautious about the broad implementation of these strategies in babies and children. At best, rapid GS leads to diagnoses in many infants in highly selected populations. It sometimes leads to beneficial and changes in management. Parents and physicians both often find these results useful. We don’t know how useful such testing will be in the general population. It is almost inevitable that genetic counseling will be more challenging in a more general population. We don’t know how often GS helps improve outcome and survival or reduce symptoms in babies who receive a molecular diagnosis. We don’t know the relative cost-effectiveness of whole genome, whole exome, or targeted panels in different populations. We don’t know the relative contribution of a molecular diagnosis to the decision to withdraw life support. Each of these concerns will require careful study of both the technology and the ethical issues to allow us to harness the potential of these new technologies while avoiding foreseeable problems. Studies are underway to see how the tests are used in general populations. These studies should generate important information to guide clinicians and policymakers. In the meantime, parents should know that genetic results sometimes confirm an already suspected dismal prognosis and sometimes yield only ambiguous findings. Anticipatory discussions should try to give parents a realistic understanding of the likely impact of a genetic diagnosis. Both doctors and parents should recognize that the clinical usefulness of diagnostic genomic testing in newborns is a work in progress. We are only a decade into the age of true genomic medicine. We still have much to learn.