Background: hidrotic ectodermal dysplasia (HED) or Clouston syndrome is a rare autosomal dominant disorder affecting the skin and its derivatives. It is characterized by the triad of nail dystrophy, alopecia, and palmoplantar hyperkeratosis. To date, all mutations have been involving in three codons: G11R, A88V and V37E in the connexin 30 (Cx30) gene have been shown to cause this disorder.
Objective: in order to analyze the mutations of the Cx30 gene in Chinese Han patients with HED.
Methods: we collected a large Chinese HED family consisting of a total of 81 individuals including 28 HED patients (14 males and 14 females). The whole coding region of Cx30 was amplified by polymerase chain reaction and products analyzed by direct sequencing, then further confirmed at the mRNA level by RT-PCR.
Results: we detected a transition, 31(G-->A), leading to a missense mutation (G11R) in genomic DNAs of 18 patients, and the point mutation was not found in 16 normal individuals in this HED family and in 188 unrelated, population-match control individuals. The transcription of mutated allele was confirmed by RT-PCR of Cx30 mRNA.
Conclusion: our data suggests that a G11R missense mutation in the Cx30 gene can cause HED in Chinese Han population and emphasizes the importance of screening for this as well as other Cx30 gene mutations in the HED.