Population-based genetic study of childhood hearing impairment in the trent region of the United Kingdom

The objective of the study was to investigate childhood hearing impairment in a population-based sample from a genetic perspective. Participants included 82 families with hearing-impaired children (aged 4-13) previously ascertained in the Trent Health Region. A questionnaire was mailed to all families, followed by a home visit and Connexin-26 35delG mutation screen. The Connexin-26 35delG mutation was identified in seven families (approximately 10 per cent of non-syndromal hearing impairment). Children of these families were significantly more likely than children with other modes of inheritance to have a profound hearing loss with a flat audiogram profile. The families of children with a significant admission to a neonatal intensive care unit were significantly less likely to have had genetic counselling. Eight families visited were found to have features suggestive of a genetic syndrome that had not been previously assigned a specific diagnosis. The study concluded that hearing-impaired children should be investigated systematically according to an agreed-upon protocol, which should include Connexin-26 35delG mutation analysis at least for those with severe-to-profound hearing loss. Sumario El objetivo de este estudio fue investigar, desde una perspectiva genética, los trastornos auditivos en niños, con base en una muestra poblacíonal. Se incluyeron 82 familias de niños hipoacúsicos (edades 4–13 años), evaluados previamente en la región de Trent. Se envió un cuestionario a todas las familias, seguido de una visita al hogar y de un tamizaje para la mutación Connexina-26 35delG. Esta mutación fue identificada en 7 familias (aproximadamente un 10% de las hipoacusias no sindrómicas). Los niños de estas familias tenían una significativa mayor propensidn a mostrar una pérdida auditiva profunda con un perfil audiométrico piano, que aquellos con otros modos de herencia. Las familias de ninos con un numero sígnificativo de admisiones a unidades de cuidados intensivos neonatales recibieron menor consejo genético. Ocho de las familias visitadas mostraron aspectos sugestivos de un síndrome genetico al que no se le ha dado un diagnóstico específico. El estudio concluye que los niños con trastornos auditivos deben ser investigados systemáticamente de acuerdo con un protocolo acor-dado, que debe incluir un análsis de la mutación Connexina-26 35delG, al menos para aquellos con perdidas severas a profundas. © 2000, Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.