Hereditary postlingual sensorineural hearing loss mapping to chromosome Xq21
E N Manolis1, R D Eavey, S Sangwatanaroj
1Department of Otolaryngology, The Massachusetts Eye and Ear Infirmary, Boston 02114, USA.
The American Journal of Otology
|September 30, 1999
Summary
This study identified a gene linked to progressive sensorineural hearing loss in a specific family. The findings refine the location of the DFN2 locus on the X chromosome, aiding future research into hereditary deafness.
Area of Science:
- Genetics
- Audiology
- Molecular Biology
Background:
- X-linked hearing loss mutations are mapped to the long arm of the X chromosome (DFN1-DFN3).
- A family with sex-linked, postlingual, progressive sensorineural hearing loss was previously mapped to Xq.
Purpose of the Study:
- To identify the genetic basis of progressive sensorineural hearing loss in a specific family.
- To refine the chromosomal location of the responsible gene for hereditary deafness.
Main Methods:
- Clinical evaluation included physical and audiometric examinations of 17 family members.
- Molecular analysis involved polymerase chain reaction (PCR) amplification and DNA fragment analysis.
- Inheritance patterns were analyzed using the MLINK computer program.
Main Results:
- Affected males exhibited severe sensorineural hearing loss (up to 100 dB); carrier females had milder loss (10-60 dB).
- The responsible gene was strongly linked to locus DXS986 (lod score = 2.3).
- The gene was localized to a 21 cM (30 MB) interval between DXS12175 and 1106, excluding DFN1 and DFN3.
Conclusions:
- The hereditary deafness in this family is most compatible with the DFN2 locus.
- The DFN2 locus is refined to a 9.2 Mb region in chromosome X band q21, between DXS990 and DXS106.
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