151. Expansion of phenotypic spectrum of MYO15A pathogenic variants to include postlingual onset of progressive partial deafness
- Author
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Jin Hee Han, Chung Lee, Mun Young Chang, Hye Rim Park, Byung Yoon Choi, Nayoung K.D. Kim, Min Young Kim, Woong-Yang Park, and Doo Yi Oh
- Subjects
0301 basic medicine ,Proband ,MYO15A ,medicine.medical_specialty ,lcsh:Internal medicine ,lcsh:QH426-470 ,Hearing loss ,Hearing Loss, Sensorineural ,Genes, Recessive ,Biology ,Myosins ,Deafness ,Polymorphism, Single Nucleotide ,Pathogenic variant ,03 medical and health sciences ,Asian People ,Molecular genetics ,Exome Sequencing ,Genetics ,medicine ,otorhinolaryngologic diseases ,Humans ,Exome ,Amino Acid Sequence ,Allele ,lcsh:RC31-1245 ,Genetics (clinical) ,Exome sequencing ,Alleles ,Phenotype ,Cochlear Implantation ,Human genetics ,Pedigree ,lcsh:Genetics ,030104 developmental biology ,medicine.symptom ,Research Article - Abstract
Background MYO15A variants, except those in the N-terminal domain, have been shown to be associated with congenital or pre-lingual severe-to-profound hearing loss (DFNB3), which ultimately requires cochlear implantation in early childhood. Recently, such variants have also been shown to possibly cause moderate-to-severe hearing loss. Herein, we also demonstrate that some MYO15A mutant alleles can cause postlingual onset of progressive partial deafness. Methods Two multiplex Korean families (SB246 and SB224), manifesting postlingual, progressive, partial deafness in an autosomal recessive fashion, were recruited. Molecular genetics testing was performed in two different pipelines, in a parallel fashion, for the SB246 family: targeted exome sequencing (TES) of 129 known deafness genes from the proband and whole exome sequencing (WES) of all affected subjects. Only the former pipeline was performed for the SB224 family. Rigorous bioinformatics analyses encompassing structural variations were executed to investigate any causative variants. Results In the SB246 family, two different molecular diagnostic pipelines provided exactly the same candidate variants: c.5504G > A (p.R1835H) in the motor domain and c.10245_10247delCTC (p.S3417del) in the FERM domain of MYO15A. In the SB224 family, c.9790C > T (p.Q3264X) and c.10263C > G (p.I3421M) in the FERM domain were detected as candidate variants. Conclusions Some recessive MYO15A variants can cause postlingual onset of progressive partial deafness. The phenotypic spectrum of DFNB3 should be extended to include such partial deafness. The mechanism for a milder phenotype could be due to the milder pathogenic potential from hypomorphic alleles of MYO15A or the presence of modifier genes. This merits further investigation. Electronic supplementary material The online version of this article (10.1186/s12881-018-0541-9) contains supplementary material, which is available to authorized users.
- Published
- 2018