A novel missense variant in MYO3A is associated with autosomal dominant high-frequency hearing loss in a German family

  • Mol Genet Genomic Med. 2020 Aug;8(8):e1343. doi: 10.1002/mgg3.1343.
Julia Doll  1 Michaela A H Hofrichter  1 Paulina Bahena  1 Alfred Heihoff  2 Dennis Segebarth  3 Tobias Müller  4 Marcus Dittrich  1  4 Thomas Haaf  1 Barbara Vona  1  5
Affiliations
  • 1. Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany.
  • 2. Joint Practice of Pediatrics, Regensburg, Germany.
  • 3. Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany.
  • 4. Institute of Bioinformatics, Julius Maximilians University, Würzburg, Germany.
  • 5. Tübingen Hearing Research Centre, Department of Otolaryngology - Head and Neck Surgery, Eberhard Karls University, Tübingen, Germany.
Abstract

Background: MYO3A, encoding the Myosin IIIA protein, is associated with autosomal recessive and autosomal dominant nonsyndromic hearing loss. To date, only two missense variants located in the motor-head domain of MYO3A have been described in autosomal dominant families with progressive, mild-to-profound sensorineural hearing loss. These variants alter the ATPase activity of Myosin IIIA.

Methods: Exome Sequencing of a proband from a three-generation German family with prelingual, moderate-to-profound, high-frequency hearing loss was performed. Segregation analysis confirmed a dominant inheritance pattern. Regression analysis of mean hearing level thresholds per individual and ear was performed at high-, mid-, and low-frequencies.

Results: A novel heterozygous missense variant c.716T>C, p.(Leu239Pro) in the kinase domain of MYO3A was identified that is predicted in silico as disease causing. High-frequency, progressive hearing loss was identified.

Conclusion: Correlation analysis of pure-tone hearing thresholds revealed progressive hearing loss, especially in the high-frequencies. In the present study, we report the first dominant likely pathogenic variant in MYO3A in a European family and further support MYO3A as an autosomal dominant hearing loss gene.

Keywords
MYO3A; autosomal dominant nonsyndromic hearing loss; myosin IIIA; progressive hearing loss; sensorineural hearing loss.