Vision Problems in Rett Could Serve as Biomarker

Mice missing the Rett syndrome gene MeCP2 show a gradual decline in vision, and too much inhibitory signaling in the visual cortex, according to unpublished research presented Thursday at Cell Symposia: Autism Spectrum Disorders: From Mechanisms to Therapies in Washington, D.C., a satellite conference of the Society for Neuroscience annual meeting. Normalizing the balance of excitatory and inhibitory signals restores the animals' sight, the researchers report.This abnormality in the visual area of the brain could be one of the first steps in a developmental cascade in the mice and, perhaps, in people with Rett syndrome, the researchers say.Preliminary research in girls with Rett suggests that clinical trials for the syndrome could track visual sharpness, or acuity, in the participants to assess a drug’s effectiveness, says Takao Hensch, professor of molecular and cellular biology at Harvard University. Hensch was presenting work led by Michela Fagiolini of Children's Hospital Boston."This is a totally objective, quantifiable measure," Hensch says. "This could be a biomarker that would indicate the efficacy of any type of treatment."Read more at...SFARI, November 2011.