PURPOSE: Hearing loss is a common congenital disorder that is frequently associated with mutations in the GJB2 gene encoding the connexin 26 protein (Cx26). We sought to evaluate the effectiveness of direct DNA sequencing for detection of Cx26 mutations as a clinical diagnostic test. METHODS: We designed a clinical assay using a three-step polymerase chain reaction (PCR)-based DNA sequencing strategy to detect all possible mutations in the open reading frame and flanking sequences of Cx26. The results of the first 324 cases of childhood deafness referred for diagnostic testing were analyzed. RESULTS: A total of 127 of the 324 (39.2%) cases had at least one mutant Cx26 allele (36.1% of sporadic cases, 70% of familial cases). Of these 127 case, 57 (44.8%) were homozygotes or compound heterozygotes. Thirty-four different mutations were identified, including 10 novel mutations, 6 of which (T8M, K15T, R32L, M93I, N206S, and 511-512insAACG) may be pathogenic. We also provide new evidence on the pathogenicity or nonpathogenicity of 12 previously reported mutations, and clarify the confusing nomenclature of the 313-326del14 mutation. CONCLUSION: A simple and rigorous method for efficient PCR-based sequence analysis of Cx26 is a sensitive clinical assay for evaluating deaf children. Its widespread use is likely to identify additional pathogenic mutations and lead to a better understanding of the clinical significance of previously identified mutations.
PURPOSE: Hearing loss is a common congenital disorder that is frequently associated with mutations in the GJB2 gene encoding the connexin 26 protein (Cx26). We sought to evaluate the effectiveness of direct DNA sequencing for detection of Cx26 mutations as a clinical diagnostic test. METHODS: We designed a clinical assay using a three-step polymerase chain reaction (PCR)-based DNA sequencing strategy to detect all possible mutations in the open reading frame and flanking sequences of Cx26. The results of the first 324 cases of childhood deafness referred for diagnostic testing were analyzed. RESULTS: A total of 127 of the 324 (39.2%) cases had at least one mutant Cx26 allele (36.1% of sporadic cases, 70% of familial cases). Of these 127 case, 57 (44.8%) were homozygotes or compound heterozygotes. Thirty-four different mutations were identified, including 10 novel mutations, 6 of which (T8M, K15T, R32L, M93I, N206S, and 511-512insAACG) may be pathogenic. We also provide new evidence on the pathogenicity or nonpathogenicity of 12 previously reported mutations, and clarify the confusing nomenclature of the 313-326del14 mutation. CONCLUSION: A simple and rigorous method for efficient PCR-based sequence analysis of Cx26 is a sensitive clinical assay for evaluating deaf children. Its widespread use is likely to identify additional pathogenic mutations and lead to a better understanding of the clinical significance of previously identified mutations.
Authors: Hsiao-Yuan Tang; Ping Fang; Patricia A Ward; Eric Schmitt; Sandra Darilek; Spiros Manolidis; John S Oghalai; Benjamin B Roa; Raye Lynn Alford Journal: Am J Med Genet A Date: 2006-11-15 Impact factor: 2.802
Authors: Juan M R Albano; Nahuel Mussini; Roxana Toriano; Julio C Facelli; Marta B Ferraro; Mónica Pickholz Journal: Comput Biol Chem Date: 2018-11-12 Impact factor: 2.877
Authors: Rikkert L Snoeckx; Patrick L M Huygen; Delphine Feldmann; Sandrine Marlin; Françoise Denoyelle; Jaroslaw Waligora; Malgorzata Mueller-Malesinska; Agneszka Pollak; Rafal Ploski; Alessandra Murgia; Eva Orzan; Pierangela Castorina; Umberto Ambrosetti; Ewa Nowakowska-Szyrwinska; Jerzy Bal; Wojciech Wiszniewski; Andreas R Janecke; Doris Nekahm-Heis; Pavel Seeman; Olga Bendova; Margaret A Kenna; Anna Frangulov; Heidi L Rehm; Mustafa Tekin; Armagan Incesulu; Hans-Henrik M Dahl; Desirée du Sart; Lucy Jenkins; Deirdre Lucas; Maria Bitner-Glindzicz; Karen B Avraham; Zippora Brownstein; Ignacio del Castillo; Felipe Moreno; Nikolaus Blin; Markus Pfister; Istvan Sziklai; Timea Toth; Philip M Kelley; Edward S Cohn; Lionel Van Maldergem; Pascale Hilbert; Anne-Françoise Roux; Michel Mondain; Lies H Hoefsloot; Cor W R J Cremers; Tuija Löppönen; Heikki Löppönen; Agnete Parving; Karen Gronskov; Iris Schrijver; Joseph Roberson; Francesca Gualandi; Alessandro Martini; Geneviéve Lina-Granade; Nathalie Pallares-Ruiz; Céu Correia; Graça Fialho; Kim Cryns; Nele Hilgert; Paul Van de Heyning; Carla J Nishimura; Richard J H Smith; Guy Van Camp Journal: Am J Hum Genet Date: 2005-10-19 Impact factor: 11.025