GJB2 Gene Testing, Etiologic Diagnosis and Genetic Counseling in Romanian Persons With Prelingual Hearing Loss

Abstract

Background: Nowadays, molecular genetic tests provide insights into the etiologic diagnosis of hearing loss (HL). Specific gene mutations are known to cause sensorineural HL of early onset. Previously published studies showed the allelic heterogeneity ofGJB2 gene as main genetic cause of isolated congenital HL. The aims of the present study were to provide an extended and updated spectrum of mutations inGJB2 gene and to identify the most prevalent mutations in the Romanian population for testing prevention strategy in people with sensorineural HL of early onset.

Methods: To overcome our aims, we used clinical data from 125 unrelated persons with congenital HL and performed ARMS-PCR and DNA sequencing techniques for detection of known mutations or identification of mutations withinGJB2 gene.

Results: The most prevalent mutation was c.35delG found in both homozygotic and heterozygotic forms. The second mutant allele was c.71G>A (p.W24X) found in homo- or heterozygotic forms as well, followed by c.-23+1G>A and c.380G>A (p.R127H) mutations with lower frequencies.

Conclusion: The study reveals the c.35delG mutation as having the highest prevalence, further highlights the genetic background of congenital HL in a local population, and supports improvement of genetic testing such as newborn and carrier screening on which to base genetic counseling services.




Int J Clin Pediatr. 2015;4(1):121-126
doi: http://dx.doi.org/10.14740/ijcp194w