BACKGROUND Usher syndrome (USH) is a genetically heterogeneous deafness-blindness syndrome, divided into three clinical subtypes: USH1, USH2 and USH3. METHODS Mutations in 21 out of 26 investigated Danish unrelated individuals with USH were identified, using a combination of molecular diagnostic methods. RESULTS Before Next Generation Sequencing (NGS) became available mutations in nine indi...

The MYO7A encodes a protein classified as an unconventional myosin. Here, we present a family with non-syndromic autosomal dominant hearing impairment that clinically resembles other previously published DFNA11 families. Affected members of the family present with an ascending audiogram affecting low and middle frequencies at young ages and then affecting all frequencies with increasing age. Ge...

Functional sensory hair cells in the inner ear have specialised microvilli — stereocilia — which are essential for hearing. The scanning electron micrograph at top shows the normal arrangement of stereocilia bundles on three outer hair cells in the inner ear of a three-day-old mouse. The stereocilia grow to form rows of graded height in a distinctive V-shaped bundle. Recent studies in mice have...

The rat is the most extensively studied model organism and is broadly used in biomedical research. Current rat disease models are selected from existing strains and their number is thereby limited by the degree of naturally occurring variation or spontaneous mutations. We have used ENU mutagenesis to increase genetic variation in laboratory rats and identified a recessive mutant, named tornado,...

PURPOSE Usher syndrome (USH) is an autosomal recessive disorder resulting in retinal degeneration and sensorineural deafness caused by mutations in at least 10 gene loci. USH is divided into three main clinical types: USH1 (33-44%), USH2 (56-67%), and USH3. Worldwide, USH1 and USH2 account for most of the Usher syndrome cases with rare occurrence of USH3. In Finland, however, USH3 is the most c...

PURPOSE To identify the genetic defect in a Hutterite population from northern Alberta with Usher syndrome type I. METHODS Complete ophthalmic examinations were conducted on two boys and two girls from two related Hutterite families diagnosed with Usher syndrome type I. DNA from patients and their parents was first evaluated for a mutation in exon 10 of the protocadherin-related 15 (PCDH15) g...