Genomic structure and identification of novel mutations in usherin, the gene responsible for Usher syndrome type IIa.

  title={Genomic structure and identification of novel mutations in usherin, the gene responsible for Usher syndrome type IIa.},
  author={Michael D. Weston and James D. Eudy and Sanae Fujita and Shun Yao and Shin‐ichi Usami and Cor W.R.J. Cremers and Jacquie L Greenberg and R. S. Ramesar and Alessandro Martini and C Moller and R J Smith and Janos Sumegi and William J. Kimberling},
  journal={American journal of human genetics},
  volume={66 4},
Usher syndrome type IIa (USHIIa) is an autosomal recessive disorder characterized by moderate to severe sensorineural hearing loss and progressive retinitis pigmentosa. This disorder maps to human chromosome 1q41. Recently, mutations in USHIIa patients were identified in a novel gene isolated from this chromosomal region. The USH2A gene encodes a protein with a predicted molecular weight of 171.5 kD and possesses laminin epidermal growth factor as well as fibronectin type III domains. These… 

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Identification of 51 novel exons of the Usher syndrome type 2A (USH2A) gene that encode multiple conserved functional domains and that are mutated in patients with Usher syndrome type II.

The presence of pathogenic mutations in the novel exons indicates that at least one of the putative long isoforms of the USH2A protein plays a role in both hearing and vision.

Identification of five novel mutations in the long isoform of the USH2A gene in Chinese families with Usher syndrome type II

The results indicate that the long isoform of USH2A may harbor even more mutations of the USH1A gene than previously thought, and broaden the spectrum of USh2A mutations.

Mutational screening of the USH2A gene in Spanish USH patients reveals 23 novel pathogenic mutations

Considering only the patients clearly diagnosed with Usher syndrome type II, and results obtained in this and previous studies, this report can state that mutations in USH2A are responsible for 76.1% of USH 2 disease in patients of Spanish origin.

Spectrum of mutations in USH2A in British patients with Usher syndrome type II.

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Mutation analysis in the long isoform of USH2A in American patients with Usher Syndrome type II

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Genetic analysis of a four generation Indian family with Usher syndrome: a novel insertion mutation in MYO7A.

DNA sequence analysis of the entire coding region of the MYO7A gene showed a novel insertion mutation c.2663_2664insA in a homozygous state in all affected individuals, resulting in truncation of MYO 7A protein.

The USH2A c.2299delG mutation: dating its common origin in a Southern European population

The data confirm the common ancestral origin of the c.2299delG mutation and suggest that the major source of variability in the USH2A gene is recombination.

Mutations in Myosin VIIA (MYO7A) and Usherin (USH2A) in Spanish patients with usher syndrome types I and II, respectively

Analysis of the MYO7A gene in patients from 30 USH1 families and sporadic cases identified 32% of disease alleles, with mutation Q821X being the most frequent, and most of the remaining variants are private mutations.

Molecular and in silico analyses of the full‐length isoform of usherin identify new pathogenic alleles in Usher type II patients

A previously unrecognized Cysteine rich structural domain is identified, containing 12 dicysteine repeats, and it is shown that three missense mutations result in the loss of one of a pair of the defining cysteine‐cysteine pairs.

Novel mutations in the long isoform of the USH2A gene in patients with Usher syndrome type II or non-syndromic retinitis pigmentosa

At least one mutation was identified in 57–63% of USH2 cases and 19–23% of cases of non-syndromic recessive RP (calculated without and including probable/possible deleterious changes) thus supporting that USH 2A is the most common known cause of RP in the USA.



Mutation of a gene encoding a protein with extracellular matrix motifs in Usher syndrome type IIa.

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Localization of the Usher syndrome type ID gene (Ush1D) to chromosome 10.

Clinical findings in the four affected children are consistent with established diagnostic criteria for Usher syndromes, and the location of the Ush1D gene was defined by the only region showing homozygosity by descent in the affected siblings.

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Assignment of an Usher syndrome type III (USH3) gene to chromosome 3q.

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A newly identified locus for Usher syndrome type I, USH1E, maps to chromosome 21q21.

Using homozygosity mapping in a consanguineous family from Morocco, a novel locus for USH1,USH1E is identified, mapping to chromosome band 21q21, and the delimited 15 cM interval is flanked by the loci D 21S1905 and D21S1913.

A novel locus for Usher syndrome type II, USH2B, maps to chromosome 3 at p23–24.2

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E210K mutation in the gene encoding the β3 chain of laminin‐5 (LAMB3) is predictive of a phenotype of generalized atrophic benign epidermolysis bullosa

Three junctional EB patients who carry an identical missense mutation, E210K, on one allele of the gene encoding the β3 subunit chain of laminin‐5 (LAMB3) in addition to different nonsense mutations on the second allele are reported.

Mutations in a human homologue of Drosophila crumbs cause retinitis pigmentosa (RP12)

The distinct RPE abnormalities observed in RP12 patients suggest that CRB1 mutations trigger a novel mechanism of photoreceptor degeneration, and a role forCRB1 in cell-cell interaction and possibly in the maintenance of cell polarity in the retina is suggested.

Localization of Usher syndrome type II to chromosome 1q.