Abstract
Usher syndrome is an autosomal recessive disorder characterized by congenital hearing impairment, progressive visual loss owing to retinitis pigmentosa and in some cases vestibular dysfunction. Usher syndrome is divided into three subtypes, USH1, USH2 and USH3. Twelve loci and eleven genes have so far been identified. Duplications and deletions in PCDH15 and USH2A that lead to USH1 and USH2, respectively, have previously been identified in patients from United Kingdom, Spain and Italy. In this study, we investigate the proportion of exon deletions and duplications in PCDH15 and USH2A in 20 USH1 and 30 USH2 patients from Denmark using multiplex ligation-dependent probe amplification (MLPA). Two heterozygous deletions were identified in USH2A, but no deletions or duplications were identified in PCDH15. Next-generation mate-pair sequencing was used to identify the exact breakpoints of the two deletions identified in USH2A. Our results suggest that USH2 is caused by USH2A exon deletions in a small fraction of the patients, whereas deletions or duplications in PCDH15 might be rare in Danish Usher patients.
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Change history
12 November 2015
This paper has been corrected since online publication and a corrigendum also appears in this issue
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Acknowledgements
We thank the families for their participation. Jette Bune Rasmussen is acknowledged for the photographic assistance. Lone Sandbjerg Hindbæk is thanked for the excellent technical help and Susan Peters for proofreading the manuscript. The NGS mate-pair analysis took place at ICMM. This work was supported by the Oticon Foundation, the Jascha Foundation, the Dag Lenard Foundation, the Augustinus Foundation, and the Director Jacob Madsen and wife Olga Madsen Foundation.
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Dad, S., Rendtorff, N., Kann, E. et al. Partial USH2A deletions contribute to Usher syndrome in Denmark. Eur J Hum Genet 23, 1646–1651 (2015). https://doi.org/10.1038/ejhg.2015.54
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DOI: https://doi.org/10.1038/ejhg.2015.54
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