GeneDx's GUARDIAN study, published in JAMA, found 3.7% of 4,000 newborns screened positive for genetic conditions undetectable by standard methods, including 120 with confirmed disorders not in traditional panels. The study screens for 255 conditions, 156 with established treatments, supported by Columbia University, NewYork-Presbyterian, and others, now expanded to 13,000 newborns and 446 genes. Similar studies are underway in the UK.