Our study looked at more than 11,500 newborns who carry genetic variants associated with deafness. Although genetic testing identified hundreds of infants at high risk for hearing loss, standard newborn hearing screenings failed to detect most of these cases—either because the babies could hear normally at birth or because the hearing loss develops later in childhood. In the end, only 58 infants were officially diagnosed with hearing loss. Interestingly, 15% of them had actually passed their initial newborn hearing screening. This points to a major gap: relying only on current hearing tests misses many children who will go on to develop hearing problems as they grow. Genetic testing offers a critical early warning. It gives families and doctors the chance to closely monitor these children and step in quickly if hearing loss begins to appear. (https://jmg.bmj.com/content/early/2026/03/23/jmg-2025-111135)