Genetic Etiology of Nonsyndromic Hearing Loss in Hungarian Patients

Int J Mol Sci. 2023 Apr 17;24(8):7401. doi: 10.3390/ijms24087401.


Hearing loss is the most prevalent sensory disorder worldwide. The majority of congenital nonsyndromic hearing loss (NSHL) cases are caused by hereditary factors. Previously, the majority of NSHL studies focused on the GJB2 gene; however, with the availability of next-generation sequencing (NGS) methods, the number of novel variants associated with NSHL has increased. The purpose of this study was to design effective genetic screening for a Hungarian population based on a pilot study with 139 NSHL patients. A stepwise, comprehensive genetic approach was developed, including bidirectional capillary sequencing, multiplex ligation-dependent probe amplification (MLPA), and an NGS panel of 108 hearing loss genes. With our results, a genetic diagnosis was possible for 92 patients. Sanger sequencing and MLPA identified the genetic background of 50% of these diagnosed cases, and the NGS panel identified another 16%. The vast majority (92%) of the diagnosed cases showed autosomal recessive inheritance and 76% were attributed to GJB2. The implementation of this stepwise analysis markedly increased our diagnostic yield and proved to be cost-effective as well.

Keywords: cochlear implants; genetic hearing loss; genetic testing.

MeSH terms

  • Connexin 26 / genetics
  • Connexins / genetics
  • Hearing Loss* / diagnosis
  • Hearing Loss* / genetics
  • Humans
  • Hungary
  • Mutation
  • Pilot Projects


  • Connexin 26
  • Connexins

Supplementary concepts

  • Nonsyndromic Deafness

Grants and funding

This research was supported by the EFOP-3.6.2-16-2017-00009 grant and by the GINOP-2.3.2-15-2016-00039 grant.