The association between GJB2 mutation and GJB6 gene in non syndromic hearing loss school children

Asma Abdullah, A. Ashwaq, Norzana Abd. Ghafar, A. Maizaton Atmadini, Ruszymah Idrus, L. Saim, Farah Wahida Ibrahim

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Recently, molecular testing for GJB2 mutations has become the standard of care for the diagnosis of patients with non syndromic hearing impairment of unknown cause. The aims of this study are to determine the association between GJB2 mutation and GJB6 and to report the variation of mutations in deaf students who have heterozygous GJB2. This retrospective study was conducted at Universiti Kebangsaan Malaysia Medical Center (UKMMC). Data was collected from previous files and records from Tissue Engineering and Human Genetic Research Group Laboratory. Approval from Ethical Committee was obtained prior to the study. A total of 138 students have been screened in previous studies in UKMMC for the presence of GJB2 mutations as a cause for hearing loss. Thirty four of the 138 subjects have GJB2 mutations; 2 showed homozygous mutations whereas another 32 were heterozygous for GJB2 gene mutation. Only 31 DNA samples of students presented with sensorineural hearing loss with heterozygous mutation in GJB2 gene were included in this study. The sequencing results obtained were analyzed. The degree of hearing loss of those students with association between GJB2 mutation and GJB6 mutation will be discussed. Five out of 31 subjects (16.2%) have mutations in their GJB6 gene, suggesting a digenic inheritance of GJB2/GJB6 mutation. In total, four novel mutations were identified; E137D (n=1), R32Q (n=1), E101K (n=1) and Y156H (n=1) and one mutation deletion; 366delT (n=1). All students with association GJB2 mutation and GJB6 showed severe to profound hearing loss in both ears. Interestingly this study not detected the large deletion of 342 kb in GJB6 gene suggesting that the mutation is very rare in this region compared to certain parts of the world.

Original languageEnglish
Pages (from-to)124-128
Number of pages5
JournalMedical Journal of Malaysia
Volume66
Issue number2
Publication statusPublished - Jun 2011

Fingerprint

Hearing Loss
Mutation
Genes
Students
Malaysia
Genetic Research
Sensorineural Hearing Loss
Sequence Deletion
Medical Genetics
Tissue Engineering
Standard of Care
Ear
Retrospective Studies

Keywords

  • Deletion
  • Gap junction
  • Gene
  • Homozygous
  • Mutation

ASJC Scopus subject areas

  • Medicine(all)

Cite this

The association between GJB2 mutation and GJB6 gene in non syndromic hearing loss school children. / Abdullah, Asma; Ashwaq, A.; Abd. Ghafar, Norzana; Maizaton Atmadini, A.; Idrus, Ruszymah; Saim, L.; Ibrahim, Farah Wahida.

In: Medical Journal of Malaysia, Vol. 66, No. 2, 06.2011, p. 124-128.

Research output: Contribution to journalArticle

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