title: Partial USH2A deletions contribute to Usher syndrome in Denmark.
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.
authors: Clinical Genetics Clinic, The Kennedy Center, Rigshospitalet, University of Copenhagen, Glostrup, Denmark.
authors: Shzeena
authors: S
authors: Dad
authors: Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.|Department of Otorhinolaryngology, Head and Neck Surgery and Audiology, Bispebjerg Hospital/Rigshospitalet, Copenhagen, Denmark.
authors: Nanna D
authors: ND
authors: Rendtorff
authors: Clinical Genetics Clinic, The Kennedy Center, Rigshospitalet, University of Copenhagen, Glostrup, Denmark.
authors: Erik
authors: E
authors: Kann
authors: Department of Biology, Computational and RNA Biology, University of Copenhagen, Copenhagen, Denmark.
authors: Anders
authors: http://orcid.org/0000-0001-7306-031X
authors: A
authors: Albrechtsen
authors: Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.
authors: Mana M
authors: MM
authors: Mehrjouy
authors: Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.
authors: Mads
authors: M
authors: Bak
authors: Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.
authors: Niels
authors: N
authors: Tommerup
authors: Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark.|Department of Otorhinolaryngology, Head and Neck Surgery and Audiology, Bispebjerg Hospital/Rigshospitalet, Copenhagen, Denmark.
authors: Lisbeth
authors: L
authors: Tranebjærg
authors: Department of Ophthalmology, The National Eye Clinic, Copenhagen University Hospital, The Kennedy Center, Glostrup, Denmark.
authors: Thomas
authors: T
authors: Rosenberg
authors: Department of Ophthalmology, The National Eye Clinic, Copenhagen University Hospital, The Kennedy Center, Glostrup, Denmark.
authors: Hanne
authors: H
authors: Jensen
authors: Clinical Genetics Clinic, The Kennedy Center, Rigshospitalet, University of Copenhagen, Glostrup, Denmark.
authors: Lisbeth B
authors: LB
authors: Møller
mesh_terms: D000070585:Cadherin Related Proteins; D015820:Cadherins / Q000235:genetics; D056905:Chromosome Breakpoints; D003718:Denmark; D005091:Exons; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D017353:Gene Deletion; D020440:Gene Duplication; D006801:Humans; D052245:Usher Syndromes / Q000235:genetics*
chemical_list: C498835:CDHR15, human; D000070585:Cadherin Related Proteins; D015820:Cadherins; D016326:Extracellular Matrix Proteins; C112735:USH2A protein, human