Several cases of widespread involvement have been reported, including one in association with the keratitis-ichthyosis-deafness (KID) syndrome (OMIM #148210), a rare disorder caused by mutations in the GJB2 gene coding for the gap junction protein connexin26 (Cx26).
The presence of a pathogenic Cx30 mutation and the lack of a pathologic molecular change in Cx26 in this patient, whose clinical features predominantly resemble KID syndrome, suggest genetic heterogeneity of KID syndrome and underscore that mutations in Cx30, similar to those in Cx26 or Cx31, can cause different phenotypes.
The presence of a pathogenic Cx30 mutation and the lack of a pathologic molecular change in Cx26 in this patient, whose clinical features predominantly resemble KID syndrome, suggest genetic heterogeneity of KID syndrome and underscore that mutations in Cx30, similar to those in Cx26 or Cx31, can cause different phenotypes.
There are significant differences in the clinical picture of two rare autosomal dominant syndromes: keratitis-ichthyosis-deafness (KID) syndrome and hidrotic ectodermal dysplasia (Clouston syndrome), which are caused by GJB2 and GJB6 mutations, respectively.
These results indicated that GJB2 mutation (p.G12R) in this case of KID syndrome, which was susceptible to T. rubrum infection, might be attributed to a limited native immune response.
These results show that these two mutations exhibit a shared gain of functional activity and support the hypothesis that increased hemichannel activity is a common feature of human Cx26 mutations responsible for KID syndrome.
This report describes a patient exhibiting characteristics suggestive of a late-onset, incomplete form of KID syndrome with the GJB2 mutation (p.G12R).
Two different connexin 26 mutations in an inbred kindred segregating non-syndromic recessive deafness: implications for genetic studies in isolated populations.