Splice-altering variant in COL11A1 as a cause of nonsyndromic hearing loss DFNA37.

Purpose: The aim of this study was to determine the genetic cause of autosomal dominant nonsyndromic hearing loss segregating in a multigenerational family.

Methods: Clinical examination, genome-wide linkage analysis, and exome sequencing were carried out on the family.

Results: Affected individuals presented with early-onset progressive mild hearing impairment with a fairly flat, gently downsloping or U-shaped audiogram configuration.

A combination of two truncating mutations in USH2A causes more severe and progressive hearing impairment in Usher syndrome type IIa.

Objectives: Usher syndrome is an inherited disorder that is characterized by hearing impairment (HI), retinitis pigmentosa, and in some cases vestibular dysfunction. Usher syndrome type IIa is caused by mutations in USH2A. HI in these patients is highly heterogeneous and the present study evaluates the effects of different types of USH2A mutations on the audiometric phenotype.

HOMER2, a stereociliary scaffolding protein, is essential for normal hearing in humans and mice.

Hereditary hearing loss is a clinically and genetically heterogeneous disorder. More than 80 genes have been implicated to date, and with the advent of targeted genomic enrichment and massively parallel sequencing (TGE+MPS) the rate of novel deafness-gene identification has accelerated. Here we report a family segregating post-lingual progressive autosomal dominant non-syndromic hearing loss (ADNSHL).

Expressivity of hearing loss in cases with Usher syndrome type IIA.

Objective: The purpose of this study was to compare the genotype/phenotype relationship between siblings with identical USH2A pathologic mutations and the consequent audiologic phenotypes, in particular degree of hearing loss (HL). Decade audiograms were also compared among two groups of affected subjects with different mutations of USH2A.

Design: DNA samples from patients with Usher syndrome type II were analysed.

Advancing genetic testing for deafness with genomic technology.

Background: Non-syndromic hearing loss (NSHL) is the most common sensory impairment in humans. Until recently its extreme genetic heterogeneity precluded comprehensive genetic testing. Using a platform that couples targeted genomic enrichment (TGE) and massively parallel sequencing (MPS) to sequence all exons of all genes implicated in NSHL, we tested 100 persons with presumed genetic NSHL and in so doing established sequencing requirements for maximum sensitivity and defined MPS quality score metrics that obviate Sanger validation of variants.

Mutation screening of the PCDH15 gene in Spanish patients with Usher syndrome type I.

Purpose: PCDH15 codes for protocadherin-15, a cell-cell adhesion protein essential in the morphogenesis and cohesion of stereocilia bundles and in the function or preservation of photoreceptor cells. Mutations in the PCDH15 gene are responsible for Usher syndrome type I (USH1F) and non-syndromic hearing loss (DFNB23). The purpose of this work was to perform PCDH15 mutation screening to identify the genetic cause of the disease in a cohort of Spanish patients with Usher syndrome type I and establish phenotype-genotype correlation.

Evidence of genetic heterogeneity in Alberta Hutterites with Usher syndrome type I.

Purpose: To identify the genetic defect in a Hutterite population from northern Alberta with Usher syndrome type I.

Methods: Complete ophthalmic examinations were conducted on two boys and two girls from two related Hutterite families diagnosed with Usher syndrome type I. DNA from patients and their parents was first evaluated for a mutation in exon 10 of the protocadherin-related 15 (PCDH15) gene (c.

Retinal disease course in Usher syndrome 1B due to MYO7A mutations.

PURPOSE. To determine the disease course in Usher syndrome type IB (USH1B) caused by myosin 7A (MYO7A) gene mutations. METHODS.

Hearing loss disorders associated with renal disease.

There are several syndromes in which both hearing and renal function are impaired. The two best known are branchio-oto-renal (BOR) syndrome and Alport syndrome. These are reviewed along with several other rarer syndromes.

Loss-of-function mutations of ILDR1 cause autosomal-recessive hearing impairment DFNB42.

By using homozygosity mapping in a consanguineous Pakistani family, we detected linkage of nonsyndromic hearing loss to a 7.6 Mb region on chromosome 3q13.31-q21.

Mutations in TMC1 are a common cause of DFNB7/11 hearing loss in the Iranian population.

Objectives: We investigated the cause of autosomal recessive nonsyndromic hearing loss (ARNSHL) that segregated in 2 consanguineous Iranian families.

Methods: Otologic and audiometric examinations were performed on affected members of each family. Genome-wide parametric multipoint linkage mapping using a recessive model was performed with Affymetrix 50K GeneChips or short tandem repeat polymorphisms.

Phenotypes in defined genotypes including siblings with Usher syndrome.

Objective: To characterize visual function in defined genotypes including siblings with Usher syndrome.

Methods: Thirteen patients with phenotypically different subtypes of Usher syndrome, including 3 families with affected siblings, were selected. Genetic analysis and ophthalmological examinations including visual fields, full-field electroretinography (ERG), multifocal electroretinography (mf ERG), and optical coherence tomography (OCT) were assessed.

A novel mutation in COCH-implications for genotype-phenotype correlations in DFNA9 hearing loss.

Objectives/hypothesis: To determine the cause of autosomal dominant hearing loss segregating in an American family.

Study Design: Family study.

Methods: Otologic and audiometric examination was performed on affected family members.

Frequency of Usher syndrome in two pediatric populations: Implications for genetic screening of deaf and hard of hearing children.

Purpose: Usher syndrome is a major cause of genetic deafness and blindness. The hearing loss is usually congenital and the retinitis pigmentosa is progressive and first noticed in early childhood to the middle teenage years. Its frequency may be underestimated.

Alteration of rod and cone function in children with Usher syndrome.

Purpose: To evaluate the retinal function, with emphasis on phenotype and rate of progression, in infants and children with different genotypes of Usher syndrome.

Methods: Fourteen children (2-10 years of age) with retinitis pigmentosa and hearing impairment were examined with full-field electroretinography (ERG) during general anesthesia, ophthalmologic examination, and genetic analysis. Five children were repeatedly examined (follow-up 5-10 years) with full-field ERG under local anesthesia and in 2 children multifocal ERG and optical coherence tomography (OCT) were performed.

Variable hearing impairment in a DFNB2 family with a novel MYO7A missense mutation.

Myosin VIIA mutations have been associated with non-syndromic hearing loss (DFNB2; DFNA11) and Usher syndrome type 1B (USH1B). We report clinical and genetic analyses of a consanguineous Iranian family segregating autosomal recessive non-syndromic hearing loss (ARNSHL). The hearing impairment was mapped to the DFNB2 locus using Affymetrix 50K GeneChips; direct sequencing of the MYO7A gene was completed.

Mutations in LOXHD1, an evolutionarily conserved stereociliary protein, disrupt hair cell function in mice and cause progressive hearing loss in humans.

Hearing loss is the most common form of sensory impairment in humans and is frequently progressive in nature. Here we link a previously uncharacterized gene to hearing impairment in mice and humans. We show that hearing loss in the ethylnitrosourea (ENU)-induced samba mouse line is caused by a mutation in Loxhd1.

Mutations in the first MyTH4 domain of MYO15A are a common cause of DFNB3 hearing loss.

Objectives: To use clinical and genetic analyses to determine the mutation causing autosomal recessive nonsyndromic hearing loss (ARNSHL) segregating in two consanguineous Iranian families.

Study Design: Family study.

Methods: Members of each family received otologic and audiometric examination for the type and extent of hearing loss.

Disease boundaries in the retina of patients with Usher syndrome caused by MYO7A gene mutations.

Purpose: To study retinal microstructure in Usher Syndrome type 1B (USH1B) caused by MYO7A mutations as a prelude to treatment initiatives.

Methods: Patients with MYO7A-USH1B (n=17; ages 5-61) were studied with optical coherence tomography. Retinal laminae across horizontal and vertical meridians were measured.

Identification of two new mutations in the GPR98 and the PDE6B genes segregating in a Tunisian family.

Autosomal recessive retinitis pigmentosa (ARRP) is a genetically heterogeneous disorder. ARRP could be associated with extraocular manifestations that define specific syndromes such as Usher syndrome (USH) characterized by retinal degeneration and congenital hearing loss (HL). The USH type II (USH2) associates RP and mild-to-moderate HL with preserved vestibular function.

Autoimmune disease in a DFNA6/14/38 family carrying a novel missense mutation in WFS1.

Most familial cases of autosomal dominant low frequency sensorineural hearing loss (LFSNHL) are attributable to mutations in the wolframin syndrome 1 (WFS1) gene at the DFNA6/14/38 locus. WFS1 mutations at this locus were first described in 2001 in six families segregating LFSNHL that was non-progressive below 2,000 Hz; the causative mutations all clustered in the C-terminal domain of the wolframin protein. Mutations in WFS1 also cause Wolfram syndrome (WS), an autosomal recessive neurodegenerative disorder defined by diabetes mellitus, optic atrophy and often deafness, while numerous single nucleotide polymorphisms (SNPs) in WFS1 have been associated with increased risk for diabetes mellitus, psychiatric illnesses and Parkinson disease.

Presence of de novo mutations in autosomal dominant polycystic kidney disease patients without family history.

Background: At the University of Colorado Health Sciences Center, on detailed questioning, approximately 10% of patients with autosomal dominant polycystic kidney disease (ADPKD) gave no family history of ADPKD. There are several explanations for this observation, including occurrence of a de novo pathogenic sequence variant or extreme phenotypic variability. To confirm de novo sequence variants, we have undertaken clinical and genetic screening of affected offspring and their parents.

Genetic counseling in Usher syndrome: linkage and mutational analysis of 10 Colombian families.

Usher Syndrome (US), an autosomal recessive disease, is characterized by retinitis pigmentosa (RP), vestibular dysfunction, and congenital sensorineural deafness. There are three recognized clinical types of the disorder. In order to improve genetic counseling for affected families, we conducted linkage analysis and DNA sequencing in 10 Colombian families with confirmed diagnosis of US (4 type I and 6 type II).

Usher syndromes due to MYO7A, PCDH15, USH2A or GPR98 mutations share retinal disease mechanism.

Usher syndrome (USH) is a genetically heterogeneous group of autosomal recessive deaf-blinding disorders. Pathophysiology leading to the blinding retinal degeneration in USH is uncertain. There is evidence for involvement of the photoreceptor cilium, photoreceptor synapse, the adjacent retinal pigment epithelium (RPE) cells, and the Crumbs protein complex, the latter implying developmental abnormalities in the retina.