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Updated: Aug 26, 2025

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
De novo variants are a common cause of genetic hearing loss
Miles J Klimara1, Carla Nishimura1, Donghong Wang1
1Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology-Head and Neck Surgery, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Iowa City, IA.
Purpose:
De novo variants (DNVs) are a well-recognized cause of genetic disorders. The contribution of DNVs to hearing loss (HL) is poorly characterized. We aimed to evaluate the rate of DNVs in HL-associated genes and assess their contribution to HL.
Methods:
Targeted genomic enrichment and massively parallel sequencing were used for molecular testing of all exons and flanking intronic sequences of known HL-associated genes, with no exclusions on the basis of type of HL or clinical features. Segregation analysis was performed, and previous reports of DNVs in PubMed and ClinVar were reviewed to characterize the rate, distribution, and spectrum of DNVs in HL.
Results:
DNVs were detected in 10% (24/238) of trios for whom segregation analysis was performed. Overall, DNVs were causative in at least ∼1% of probands for whom a genetic diagnosis was resolved, with marked variability based on inheritance mode and phenotype. DNVs of MITF were most common (21% of DNVs), followed by GATA3 (13%), STRC (13%), and ACTG1 (8%). Review of reported DNVs revealed gene-specific variability in contribution of DNV to the mutational spectrum of HL-associated genes.
Conclusion:
DNVs are a relatively common cause of genetic HL and must be considered in all cases of sporadic HL.
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