DEAFNESS, AUTOSOMAL DOMINANT 30; DFNA30

Cytogenetic location: 15q25-q26 Genomic coordinates (GRCh38): 15:84,700,000-101,991,189

▼ Clinical Features
Mangino et al. (2001) reported a 4-generation Italian family segregating autosomal dominant progressive nonsyndromic hearing loss. Onset occurred between 10 and 40 years of age. Deafness first involved the higher frequencies and progressed to middle frequencies, resulting in a characteristic sloping audiogram.

▼ Mapping
Mangino et al. (2001) performed a genome scan with polymorphic microsatellite markers in an Italian family segregating autosomal dominant nonsyndromic hearing loss and mapped the disorder, designated DFNA30, to an 18-cM region on 15q25-q26 with a maximum 2-point lod score of 4.12 at theta = 0.00 for marker D15S1004. Haplotype and multipoint analysis identified a critical interval between markers D15S151 and D15S130. The critical region did not overlap with the DFNB16 locus (603720) but partially coincided with the otosclerosis-1 locus (OTSC1; 166800), leading the authors to suggest that the DFNA30 hearing impairment might be an allelic disease of OTSC1.

▼ Molecular Genetics
By sequence analysis of candidate genes mapping to the DFNA30 interval in members of an Italian family segregating nonsyndromic hearing loss, Mangino et al. (2001) found no mutations in the aggrecan-1 (155760) and PTD014 genes.