Talk Description
Institution: Children's Health Queensland - Queensland, Australia
Aim:
To characterise the genomic landscape of paediatric hearing loss (HL) in Queensland and the audiological phenotype associated with specific genes/genotypes in syndromic and non-syndromic HL.
Methodology:
A retrospective chart audit was conducted of children referred for genetic testing for HL at the statewide tertiary service (Genetic Health Queensland) and/or tested positive for GJB2 between 2014-2024. Demographic information, hearing screening outcomes, and 4-frequency audiogram (initial and most recent) were extracted. Testing results and modality (single gene, gene panel, whole exome sequencing and whole genome sequencing) were extracted, and results were divided into syndromic and non-syndromic. Audiograms were grouped and plotted relative to individual genes. Phenotypic associations were descriptively characterised and analysed by configuration and severity for each gene.
Results:
The statewide tertiary service tested 267 individuals, of whom 104 tested positive for 48 different causal genes. 44 cases (42%) received a genetic diagnosis before age 2. Additionally, paediatricians and ENTs returned 206 positive GJB2 results. Of the 310 positive cases, most (n=236, 76%) were non-syndromic, and the remainder were syndromic group (n=57, 18%) or uncertain (n=17, 6%). Ushers (n=14/57, 25%) and Waardenburg (n=14/57, 25%) were the most common syndromes while GJB2, STRC, MITF, USH2A, and SLC26A4 were the most common implicated genes. The audiological phenotype of GJB2 and USH2A ranged from mild to severe, while individuals with STRC had predominantly moderate HL.
Conclusion:
This is the first Australian study to genomically characterise paediatric HL in childhood, but the proportion of positive results which are non-syndromic and syndromic are consistent with international studies. Furthermore, although GJB2 in the most frequently implicated gene, there is significant genetic heterogeneity in individuals offered panel, exome and genomic testing, which can inform management of HL and non-audiological features.
Presenters
Authors
Authors
Dr Karen Liddle - , Ms Lucy Burbury - , Dr Chirag Patel - , Dr Rachael Beswick - , A/Prof Valerie Sung - , A/Prof Aideen Mcinerney-Leo -
