0000000000681850
AUTHOR
María José Aparisi
Study of USH1 Splicing Variants through Minigenes and Transcript Analysis from Nasal Epithelial Cells
Usher syndrome type I (USH1) is an autosomal recessive disorder characterized by congenital profound deafness, vestibular areflexia and prepubertal retinitis pigmentosa. The first purpose of this study was to determine the pathologic nature of eighteen USH1 putative splicing variants found in our series and their effect in the splicing process by minigene assays. These variants were selected according to bioinformatic analysis. The second aim was to analyze the USH1 transcripts, obtained from nasal epithelial cells samples of our patients, in order to corroborate the observed effect of mutations by minigenes in patient’s tissues. The last objective was to evaluate the nasal ciliary beat fre…
Mutational screening of the USH2A gene in Spanish USH patients reveals 23 novel pathogenic mutations
Abstract Background Usher Syndrome type II (USH2) is an autosomal recessive disorder, characterized by moderate to severe hearing impairment and retinitis pigmentosa (RP). Among the three genes implicated, mutations in the USH2A gene account for 74-90% of the USH2 cases. Methods To identify the genetic cause of the disease and determine the frequency of USH2A mutations in a cohort of 88 unrelated USH Spanish patients, we carried out a mutation screening of the 72 coding exons of this gene by direct sequencing. Moreover, we performed functional minigene studies for those changes that were predicted to affect splicing. Results As a result, a total of 144 DNA sequence variants were identified.…
Functional analysis of splicing mutations in MYO7A and USH2A genes.
Usher syndrome is defined by the association of sensorineural hearing loss, retinitis pigmentosa and variable vestibular dysfunction. Many disease-causative mutations have been identified in MYO7A and USH2A genes, which play a major role in Usher syndrome type I and type II, respectively. The pathogenic nature of mutations that lead to premature stop codons is not questioned; nevertheless, additional studies are needed to verify the pathogenicity of some changes such as those putatively involved in the splice process. Five putative splice-site variants were detected in our cohort of patients: c.2283-1G>T and c.5856G>A in MYO7A and c.1841-2A>G, c.2167+5G>A and c.5298+1G>C in the USH2A gene. …
Microarray-based mutation analysis of 183 Spanish families with Usher syndrome.
PURPOSE. The purpose of this study was to test the ability of the genotyping microarray for Usher syndrome (USH) to identify the mutations responsible for the disease in a cohort of 183 patients with USH. METHODS. DNA from 183 patients with Usher syndrome from the Spanish population was analyzed using a genotyping microarray containing 429 previously identified disease-associated variants in eight USH genes. Mutations detected by the array were confirmed by direct sequencing. Haplotype analysis was also performed in families carrying common Spanish mutations. RESULTS. The genotyping microarray identified 43 different variants, divided into 32 disease causative and 11 probably non-pathologic…