FIGURES AND TABLES

Figure 1.

Pedigree of the Belgian family 1 with non-syndromic autosomal dominant hearing loss. The haplotypes are shown below each symbol, with the linked haplotype indicated by a box. Black symbols indicate affected individuals, open symbols represent unaffected individuals and question marks indicate individuals with an uncertain diagnosis. The analyzed markers are listed from centromere (top) to telomere (bottom).

Figure 2.

Pedigree of the Belgian family 2 with non-syndromic autosomal dominant hearing loss. The haplotypes are shown below each symbol, with the linked haplotype indicated by a box. Black symbols indicate affected individuals, open symbols represent unaffected individuals and question marks indicate individuals with an uncertain diagnosis. Individual VI:1 has congenital hearing loss and carries the splice-site mutation. The analyzed markers are listed from centromere (top) to telomere (bottom).

Figure 3.

Air conduction hearing thresholds of the best ear of five patients of each family. (a) Family 1; (b) family 2; y=years.

Figure 4.

RT-PCR of a fragment containing the cryptic exon in family 2. RNA was obtained from lymphoblasts. Two separate bands could be identified for both patients, but for none of the unaffected family members: the wild-type fragment and a fragment about 100 bp larger, containing the cryptic exon. (a) PCR obtained by using primer set 1, showing the wild-type fragment of 1141 bp and the larger fragment of 1240 bp. (b) Nested PCR by use of primer set 2 and nested primer set 3, resulting in a 161 bp wild-type fragment and a 269 bp fragment carrying the mutation. Above the 269 bp fragment, another fragment was visible, but we did not succeed in sequencing this fragment to obtain the exact sequence.

Figure 5.

Genomic sequence of part of exon 23, intron 23 and exon 24, including the splice-site mutation c.IVS23+2321T>G (arrow). The boxed sequence is the coding region of exons 23 and 24. The nucleotides indicated in bold are the cryptic splice sites and the underlined sequence is the cryptic exon itself.

Table 1 - Mutations in MYO6 causing dominant and recessive hearing loss, with the corresponding phenotypes of the patients.