Audiologic aspects of the search for DFNA20: a gene causing late-onset, progressive, sensorineural hearing loss.
OBJECTIVE
The purpose of this research was to identify the gene responsible for a novel form of nonsyndromic, late-onset, bilateral, progressive, sensorineural hearing loss in a Michigan family of English descent. This report describes the audiologic aspects of the search.


METHODS
Fifty-eight members of the family served as subjects for the study. Family pedigree information was gathered from family interviews, family records, birth and death registration records and census data. Audiologic evaluation was used to describe the hearing loss (phenotype) and classify family members as affected or unaffected based on hearing status. These data then were used in a linkage analysis, a process in which the inheritance of a trait is compared with the inheritance of genetic markers and statistically significant associations are sought.


RESULTS
The team mapped the hearing loss to the long arm of chromosome 17 at band 17q25. The pattern of inheritance is autosomal dominant. The search for the gene is continuing using a candidate gene approach.


CONCLUSIONS
The hearing loss demonstrated by this mid-Michigan family is a novel form of nonsyndromic, genetic, late-onset, bilateral, progressive, sensorineural hearing loss. The locus of the gene, the 20th for autosomal dominant hearing loss, is at band 17q25 of chromosome 17.
Elfenbein
J L
JL
Department of Audiology and Speech Sciences, Michigan State University, East Lansing 48824, USA.
Fisher
R A
RA
Wei
S
S
Morell
R J
RJ
Stewart
C
C
Friedman
T B
TB
Friderici
K
K
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology; D001844:Bone Conduction / Q000502:physiology; D002352:Carrier Proteins / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D003051:Cochlea / Q000503:physiopathology; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D008040:Genetic Linkage; D006319:Hearing Loss, Sensorineural / Q000453:epidemiology / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology; D010375:Pedigree; D017354:Point Mutation / Q000235:genetics
D002352:Carrier Proteins