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The Connexin-deafness homepage

 

Last Update: 20/03/2019

 

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  Introduction
  Connexins and deafness
     - GJB2 (Cx26)
     - GJB3 (Cx31)
     - GJB6 (Cx30)
     - GJB1 (Cx32)
  Mutations databases
     - Nonsyndromic deafness           mutations
     - Syndromic deafness           mutations
     - Frequent mutations
     - Other disease mutations
     - Big deletions or           insertions
  Polymorphisms
     - GJB2 (Cx26)
     - GJB3 (Cx31)
     - GJB6 (Cx30)
  Search engine
  Submit a new mutation
  Reference list
  Links
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Frequent mutations in Cx26


There are some mutations in GJB2 that have been described in several patients, and for a few of them populational data has been collected, especially for mutations 35delG and 167delT and 235delC, which have been found to be very common in Caucasoid, Ashkenazi Jewish and Oriental populations respectively. The relative frequence of any of these mutations in a particular population is relevant to develop specific analytical systems.

Mutation 35delG has a carrier frequency in the Caucasoid population of 1/31, and 1/35 as determined by Estivill et al. (1998), Lench et al. (1998b) and  Gasparini et al.(2000) respectively.

Mutation 167delT has a carrier frequency in the Ashkenazi jew population of 4% as determined by Morell et al. 1998, while frequence of 35delG in this population, also determined by Morell et al.1998 is 0.7%.

Mutation 235delC has been detected in the Japanese population (Fuse et al. (1999), Kudo et al. (2000), Abe et al. (2000)), and in the Chinese population (Zheng et al. P.C.), accounting in all cases for the most part of mutated alleles in deaf patients. The frequency for this mutation in the Japanese population has been determined as 2/203 by Fuse et al. (1999). None of these studies identifies mutation 35delG.

Mutation M34T is also quite frequent in some populations. The carrier frequence for this mutation in the Belgian population, determined by Hilbert et al. is 2.4%. Another two carrier screenings for M34T on caucasoid populations performed by Kelley et al. 1998 and Scott et al. (1998a, 1998b) reported a frequence of 3/192 and 1/200, respectively.

To find if a mutation has been identified by several authors in different populations,
and, if published, the frequences of the mutation in each population,
click on the "other" feature in the "reference" field of the desired mutation.