The present invention provides new strategies for the treatment of Rett Syndrome and other MECP2-associated disorders, including for the identification and/or characterization of useful therapeutic modalities and/or for the stratification of Rett Syndrome patients to identify those more or less likely to respond to a particular therapy. In some embodiments, the present invention defines certain components of metabolic pathways, and particularly of lipid and/or cholesterol metabolism (e.g., biosynthesis) pathways, most particularly of lipid and/or cholesterol metabolism (e.g., biosynthesis) pathways in the brain, as targets useful in the identification and/or characterization of potential Rett Syndrome treatment agents. Among other things, the present invention provides systems for identifying and/or characterizing such agents by contacting them with a system that comprises one or more such metabolic pathway components, and assessing their impact on presence, level, activity, and/or form of one or more indicators (e.g., components, products, and/or markers of the relevant pathway(s)).
