Abstract
Deafness is the most common form of sensory impairment in humans and is frequently caused by single gene mutations. Interestingly, different mutations in a gene can cause syndromic and nonsyndromic forms of deafness, as well as progressive and age-related hearing loss. We provide here an explanation for the phenotypic variability associated with mutationsin the cadherin 23 gene (CDH23). CDH23 null alleles cause deaf-blindness (Usher syndrome type 1D; USH1D), whereas missense mutations cause nonsyndromic deafness (DFNB12). In a forward genetic screen, we have identified salsa mice, which suffer from hearing loss due to a Cdh23 missense mutation modeling DFNB12. In contrast to waltzer mice, which carry a CDH23 null allele mimicking USH1D, hair cell development is unaffected in salsa mice. Instead, tip links, which are thoughttogate mechanotransduction channelsinhair cells, are progressively lost. Our findings suggest that DFNB12 belongs to a new class of disorder that is caused by defects in tip links. We propose that mutations in other genes that cause USH1 and nonsyndromic deafness may also have distinct effects on hair cell development and function.
Original language | English (US) |
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Pages (from-to) | 5252-5257 |
Number of pages | 6 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 106 |
Issue number | 13 |
DOIs | |
State | Published - Mar 31 2009 |
Externally published | Yes |
Keywords
- Cadherin 23
- Cdh23
- Progressive hearing loss
- Usher syndrome
ASJC Scopus subject areas
- General