Purpose: To identify the genetic defect in a German family with Usher syndrome (USH) and linkage to the USH3A locus.
Methods: DNA samples of five family members (both parents and the three patients) were genotyped with polymorphic microsatellite markers specific for eight USH genes. Three affected family members underwent detailed ocular and audiologic characterization.
Results: Symptoms in the patients were compatible with Usher syndrome and show intrafamilial variation, for both hearing loss (ranging from severe to profound with non-linear progression) and vision. Genotyping of microsatellite markers for the different USH loci was in line with a defect in the USH3A gene on chromosome 3q25. Sequence analysis of the USH3A gene revealed two truncating mutations; c.149_152delCAGGinsTGTCCAAT, which has been described previously, and a novel mutation, c.502_503insA, segregating with the phenotype.
Conclusions: To date, only 11 USH3A mutations have been described. This is the first description of a German family with USH due to USH3A mutations, including one novel. Our findings indicate that also in the Central European population, USH3A mutations should be considered in cases of USH.
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Orphanet J Rare Dis
September 2024
Department of Otolaryngology-Head and Neck Surgery, Lanzhou University Second Hospital, No. 82 Cuiyingmen, Lanzhou, Gansu, 730030, PR China.
bioRxiv
March 2024
Department Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226.
Mutations in cause Usher syndrome type IIIA (USH3A), an autosomal recessive disorder characterized by hearing and vision loss, and often accompanied by vestibular balance issues. The identity of the cell types responsible for the pathology and mechanisms leading to vision loss in USH3A remains elusive. To address this, we employed CRISPR/Cas9 technology to delete a large region in the coding and untranslated (UTR) region of zebrafish .
View Article and Find Full Text PDFMol Ther Nucleic Acids
September 2020
Center for Integrated Protein Science Munich CIPSM, Munich, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany. Electronic address:
Mutations in CLRN1 cause Usher syndrome (USH) type III (USH3A), a disease characterized by progressive hearing impairment, retinitis pigmentosa, and vestibular dysfunction. Due to the lack of appropriate disease models, no efficient therapy for retinitis pigmentosa in USH patients exists so far. In addition, given the yet undefined functional role and expression of the different CLRN1 splice isoforms in the retina, non-causative therapies such as gene supplementation are unsuitable at this stage.
View Article and Find Full Text PDFDeafblindness is mostly due to Usher syndrome caused by recessive mutations in the known genes. Mutation-negative patients therefore either have distinct diseases, mutations in yet unknown Usher genes or in extra-exonic parts of the known genes - to date a largely unexplored possibility. In a consanguineous Saudi family segregating Usher syndrome type 1 (USH1), NGS of genes for Usher syndrome, deafness and retinal dystrophy and subsequent whole-exome sequencing each failed to identify a mutation.
View Article and Find Full Text PDFPLoS One
August 2016
Ophthalmology, University of Florida, Gainesville, FL, United States of America.
Usher syndrome type III (USH3A) is an autosomal recessive disorder caused by mutations in clarin-1 (CLRN1) gene, leading to progressive retinal degeneration and sensorineural deafness. Efforts to develop therapies for preventing photoreceptor cell loss are hampered by the lack of a retinal phenotype in the existing USH3 mouse models and by conflicting reports regarding the endogenous retinal localization of clarin-1, a transmembrane protein of unknown function. In this study, we used an AAV-based approach to express CLRN1 in the mouse retina in order to determine the pattern of its subcellular localization in different cell types.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!