EN
The evidence from literature strongly suggests that Christ-Siemens-Touraine (CST) syndrome is associated with mutations of the newly discovered EDA gene. The gene is situated on the long arm of the X chromosome (Xq12.2-q13.1) and contains two exons separated by a 200 kbp intron. The 5’-untranslated region and most of the coding sequence are localized in exon 1, while three C-terminal amino acids are encoded by exon 2. The coding sequence was interrupted by translocations in three affected females: t(X;l), t(X;12), t(X;9), and submicroscopic deletions of the EDA gene were found in five males with CST syndrome, and point mutations were discovered in exon 1 in nine other patients. Northern blot analysis and in situ hybridization studies revealed that the EDA gene was expressed in the foetus, and postnatally in a specific type of skin cell and that the expression was limited to cells of ectodermal origin. A predicted protein product of the EDA gene contains 135 to 140 amino acids, organized in three distinct domains and may belong to class II transmembrane receptors.