목적: Asymmetric hearing loss (AHL) is frequently observed in pediatric outpatient settings, with variable etiologies harboring genetic factors, congenital cytomegalovirus (CMV) infection, inner ear anomalies, and brain tumors. While identifying a definitive cause is crucial for guiding clinical management, many cases remain undiagnosed. Recent advances in sequencing technologies have increasingly highlighted a genetic basis for AHL. To demonstrate this, we investigated the prevalence of both classic AHL and cases with interaural asymmetry in a large sensorineural hearing loss (SNHL) cohort. We also examined how genetic factors influence the natural progression of hearing loss in the better ear. 방법:From March 2021 to November 2024, we reviewed 830 families with SNHL who underwent whole-exome or whole-genome sequencing. Only children under 18 years of age were included, excluding those with potential confounding factors such as iatrogenic trauma and brain tumors. Patients with multiple disabilities, single-sided deafness, or mixed hearing loss were also excluded. Ultimately, 354 patients met the inclusion criteria. These were stratified into Group 1, comprising individuals with AHL or symmetric hearing loss, and Group 2, which was further categorized by the degree of interaural asymmetry (0–15 dB, 15–30 dB, and >30 dB). Linear regression analysis was used to assess the natural progression of hearing loss. 결과:In Group 1, 10 (52.6%) patients with AHL and 197 (58.81%) with symmetric hearing loss received a genetic diagnosis. In Group 2, genetic diagnoses were identified in 177 (60.62%) patients with 0–15 dB asymmetry, 20 (54.05%) with 15–30 dB asymmetry, and 8 (33.33%) with >30 dB asymmetry. GJB2, SLC26A4, and CDH23 were the most prevalent genetic causes for both AHL and interaural asymmetry, with SLC26A4 predominating in >30 dB interaural asymmetry cases. Other genes, including LMX1A, LOXHD1, MYH9 and MYO15A, also contributed to AHL and interaural asymmetry. Linear regression analysis revealed a progressive decline in hearing thresholds over time in genetically diagnosed patients, varying according to the specific genetic etiology. Conversely, no consistent trend was observed in genetically undiagnosed patients. 결론:This study demonstrates the genetic contribution to AHL and interaural asymmetry in children. We observed an inverse correlation between genetic diagnosis rates and the increasing interaural asymmetry. Furthermore, genetic factors play a crucial role in shaping the prognosis of hearing loss. These findings provide the importance of genetic diagnosis in children with AHL and interaural asymmetry.