Rett syndrome (RTT) is a genetic encephalopathy and the typical form is caused by mutations
in the gene MECP2. It is a genetically heterogeneous pathology. CDKL5 and FOXG1 have been
recently discovered being involved in other forms of RTT. However, at least 5% of typical
forms and more other atypical forms are not linked to any of 3 genes known to be involved in
The purpose of this study is to identify new genes involved in molecular etiology of typical
and atypical forms of RTT.