Longevity in Rett syndrome

Although the clinical phenotype of Rett syndrome (RTT) has been known for over 40 years, it is only recently that the condition has been linked to mutations in the methyl-CpG-binding protein 2 (MECP2) gene. As has been the case with disorders such as Williams' syndrome and velocardiofacial syndrome, the availability of molecular testing for RTT has somewhat broadened the clinical picture of a disorder, which, until recently, was diagnosed entirely by clinical criteria.