| Mutation type*1 | Mutation position | Length of affected nucleotides | Nucleotide sequence after mutation | Mutation name | Case # | Consequence | Disease | Symptom | Hereditary Pattern*2 | Zygousity | Mutation Position | Onset | Progress | Ethnic Origin | Author |
| M | 151 | 1 | T | P51S | 3 | CCA-TCA at ntd 208 -> Pro-Ser at codon 51 | DFNA9, Deafness, non-syndromic, autosomal dominant | audiogram: predominant hearing impairment highfrequencies, expanding to all frequencies at a later stage. | AD | heterozygous | exon 4. situated between cysteins and possibly interferes with proper COCH protein folding or its interection with extracellular matrix proteins. | 30-45y | progressive (very rapid) | South Netherland | de kok,Y.J. et al. Hum.Mol.Genet. 8,361(1999) |
| M | 151 | 1 | T | P51S | 1 | CCA-TCA at ntd 208 -> Pro-Ser at codon 51 | DFNA9, Deafness, non-syndromic, autosomal dominant | audiogram: predominant hearing impairment highfrequencies, expanding to all frequencies at a later stage. | AD | heterozygous | exon 4. situated between cysteins and possibly interferes with proper COCH protein folding or its interection with extracellular matrix proteins. | 36-42y | progressive (very rapid) | Dutch | de kok,Y.J. et al. Hum.Mol.Genet. 8,361(1999) |
| M | 197 | 1 | G | V66G | 1 | GTA-GGA at ntd 253 -> Val-Gly at codon 66 | DFNA9, Deafness, non-syndromic, autosomal dominant | Hearing threshold: 250-800Hz. | AD | heterozygous | exon 4. A region contains four conserved cysteins with homology to a domain in Limulus factor C | 20y(16-28y) | progressive | North American | Robertson,N.G. et al. Nat.Genet. 20,299(1998) |
| M | 263 | 1 | A | G88E | 1 | GGA-GAA at ntd 319 -> Gly-Glu at codon 88 | DFNA9, Deafness, non-syndromic, autosomal dominant | high-frequencies being affected first, followed by middle and low frequencies. They become deaf in 20-40y | AD | heterozygous | exon 5. A region contains four conserved cysteins with homology to a domain in Limulus factor C | eary 20y | progressive | North American | Robertson,N.G. et al. Nat.Genet. 20,299(1998) |
| M | 349 | 1 | C | W117R | 1 | TGG-CGG at ntd 405 -> Trp-Arg at codon 117 | DFNA9, Deafness, non-syndromic, autosomal dominant | initially more profound at highfrequencies, variable progression to anacusis by 40-50y. | AD | heterozygous | exon 5. A region contains four conserved cysteins with homology to a domain in Limulus factor C | 20-30y | progressive | North American | Robertson,N.G. et al. Nat.Genet. 20,299(1998) |