Clinical and genetic characterisation of childhood-onset sensorineural hearing loss reveal associated phenotypes and enrichment of pathogenic founder mutations in the Finnish population.

To examine the clinical and genetic characteristics of childhood-onset bilateral sensorineural hearing loss (SNHL) in Finland. Retrospective analysis. A total of 249 children younger than 18 years were diagnosed with bilateral SNHL in Oulu University Hospital, Finland, from 2017 to 2022. Pathogenic or likely pathogenic gene variants or chromosome abnormalities explaining SNHL were identified in 41% ( SNHL is genetically and clinically heterogeneous. Pathogenic variants in