title: Identification of three novel TECTA mutations in Iranian families with autosomal recessive nonsyndromic hearing impairment at the DFNB21 locus.
abstract: Forty-five consanguineous Iranian families segregating autosomal recessive nonsyndromic hearing loss (ARNSHL) and negative for mutations at the DFNB1 locus were screened for allele segregation consistent with homozygosity by descent (HBD) at the DFNB21 locus. In three families demonstrating HBD at this locus, mutation screening of TECTA led to the identification of three novel homozygous mutations: one frameshift mutation (266delT), a transversion of a cytosine to an adenine (5,211C > A) leading to a stop codon, and a 9.6 kb deletion removing exon 10. In total, six mutations in TECTA have now been described in families segregating ARNSHL. All of these mutations are inactivating and produce a similar phenotype that is characterized by moderate-to-severe hearing loss across frequencies with a mid frequency dip. The truncating nature of these mutations is consistent with loss-of-function, and therefore the existing TECTA knockout mouse mutant represents a good model in which to study DFNB21-related deafness.
authors: Department of Otolaryngology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242, USA.
authors: Nicole C
authors: NC
authors: Meyer
authors: Fatemeh
authors: F
authors: Alasti
authors: Carla J
authors: CJ
authors: Nishimura
authors: Parisa
authors: P
authors: Imanirad
authors: Kimia
authors: K
authors: Kahrizi
authors: Yasser
authors: Y
authors: Riazalhosseini
authors: Mahdi
authors: M
authors: Malekpour
authors: Nafiseh
authors: N
authors: Kochakian
authors: Payman
authors: P
authors: Jamali
authors: Guy
authors: G
authors: Van Camp
authors: Richard J H
authors: RJ
authors: Smith
authors: Hossein
authors: H
authors: Najmabadi
mesh_terms: D001299:Audiometry; D001483:Base Sequence; D000072259:Connexin 26; D017630:Connexins; D003241:Consanguinity; D004252:DNA Mutational Analysis; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D005192:Family Health; D058851:GPI-Linked Proteins; D005808:Genes, Recessive; D005838:Genotype; D006319:Hearing Loss, Sensorineural / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D007492:Iran; D008562:Membrane Glycoproteins / Q000235:genetics*; D009154:Mutation; D010375:Pedigree; D012689:Sequence Homology, Nucleic Acid
chemical_list: D017630:Connexins; D016326:Extracellular Matrix Proteins; C000607042:GJB2 protein, human; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; C491350:TECTA protein, human; D000072259:Connexin 26