Mutational analysis of the MECP2 gene in Tunisian patients with Rett syndrome: a novel double mutation.

Rett syndrome is a severe disorder characterized by loss of acquired skills after a period of normal development in infant girls. It is caused mainly by mutations in the MECP2 gene. In this study, we reported mutations in the MECP2 gene in 7 Tunisian patients with classic Rett syndrome. The results showed the presence of a double mutation in 1 patient: p.R306C and c.1461+98insA, which create a new hypothetical polyadenylation site in the 3(')UTR of the MECP2 gene. We also detected in another patient a new variant c.1461+92C>G in the 3(')UTR located previous to 34 bp from the polyadenylation site with a score of 4.085. This variation is located in a hypothetical splicing enhancer with a score of 1.96277 according to the ESE finder program. In the remaining 5 patients, we found 2 common mutations: p.T158M in 4 individuals and p.R168X in only 1 girl.