MECP2 and Rett syndrome: Cytotoxic necrotizing factor 1 (CNF1), a protein toxin produced by some pathogenic Escherichia coli, has been reported to improve the behavioural phenotype and to revert the atrophy in astrocytes in a mouse model of RTT carrying a truncating mutation of the Mecp2 gene, Mecp2‐308 mice.18