Table-I: Variation detected in GJB2
, MYO7A and CDH23 genes in both brothers.
Hood, "Mutations in the connexin 26 gene (GJB2
) among Ashkenazi jews with nonsyndromic recessive deafness," The New England Journal of Medicine, vol.
Guo, "Associations between GJB2
, mitochondrial 12S rRNA, SLC26A4 mutations, and hearing loss among three ethnicities," BioMed Research International, vol.
Genetic Linkage Analysis of DFNB3, DFNB9 and DFNB21 Loci in GJB2
Negative Families with Autosomal Recessive Non-syndromic Hearing Loss.
It is known that mutations in the GJB2
gene have a significant role in non-syndromic hearing loss.
35delG mutation takes place by deletion of one guanine (G) in a run of six guanines extending from position 30 to position 35 in the GJB2
gene causing a frameshift of the coding sequence leading to premature chain termination at the twelfth amino acid .
No mutations in connexin genes GJB2
, GJB6 or GJA1 among Cameroonians and Xhosa South Africans
Neste estudo, todos os casos com etiologia genetica confirmada apresentaram a mutacao 35delG, no gene GJB2
, em homozigoze.
Los mismos autores establecieron significativas frecuencias de mutaciones en genes que codifican para conexinas (gJB2
Human connexin 26 (GJB2
) deafness mutations affect the function of gap junction channels at different levels of protein expression.
A total of 15% had congenital CMV infection and 24% had GJB2
A deafness-causing gene, GJB2
, was identified in 1997 that encodes an inner ear connexin protein called connexin 26 (Cx26), forming part of the potassium-recycling pathway used to maintain the osmotic balance essential for normal auditory function (McGuirt & Smith, 1999).