ALT Diagram showing two gauges (like a car's fuel gauge) on the left and right side. Each gauge has 3 sections: on the left, a white-background section that says "Rett syndrome"; in the middle/top, a green-background section that says "Normal"; on the right, a red-background section that says "MECP2 Duplication syndrome." A mouse below each gauge is labeled "MeCP2" and has 2 hands (gauge hands, like clock hands) above it pointing to different parts of the gauge. The left gauge indicates that loss of function of MeCP2 can be rescued with a MECP2 transgene to yield a "normal" phenotype, but the right gauge shows that partial loss-of-function in MeCP2 and subsequent rescue with MECP2 transgene results in symptoms like those of the MECP2 Duplication syndrome.