Prevalence of GJB2 and TECTA gene mutations in children with non-syndromic hearing loss visiting an Otorhino-laryngology Hospital in Ho Chi Minh City, Viet Nam

Abstract

Introduction: Non-syndromic hearing loss (NSHL) in children, which has numerous causes, can impede or even postpone the acquisition of spoken language. In Viet Nam, screening programs and genetic testing for NSHL are rarely applied. In this study, 31 pediatric patients had their medical histories collected alongside sequencing results for the GJB2 and TECTA genes to determine the prevalence of these mutations in the community and their associations with potential risk factors.

Methods: Information and blood samples were collected from 31 severe-to-profound pediatric NSHL patients. DNA was extracted, amplified by polymerase chain reaction (PCR), and directly sequenced for the detection of GJB2 (connexin 26) and TECTA mutations.

Results: No TECTA gene mutations were detected. GJB2 mutations were identified in eight patients (25.8%), with three (9.7%) cases of heterozygous c.109G>A (V37I), four (12.9%) cases of homozygous c.109G>A (V37I), and one (3.2%) case of heterozygous c.299-300delAT. There were no significant associations between having mutated GJB2 genes and living in urban areas, having a family history of prelingual deafness, or having an abnormal obstetric history (p > 0.05, Fisher's exact tests).

Conclusion: Our study addresses the high prevalence of GJB2 mutations as causative factors in hearing loss in diagnosed patients at the Otorhino-laryngology Hospital in Ho Chi Minh City, Viet Nam. Further studies are required to obtain a better understanding of the genetic spectrum of NSHL and to articulate its relationship with various risk factors.