Blocking the expression of the MeCP2 gene decreases the number of synapses, the junctions between neurons. It also prevents synapses from scaling up their activity to make up for the loss, according to unpublished data shown yesterday at the Society for Neuroscience annual meeting in San Diego.

The gene-environment interactions that are thought to contribute to many cases of autism can now be explored in a mouse model, according to a poster presented Sunday at the Society for Neuroscience annual meeting in San Diego.

A new mouse model for Rett syndrome shows that disrupting a single brain messenger can produce nearly all of the characteristic features of the syndrome, researchers report today in Nature.

A tumor suppressor best known for its role in colorectal cancer plays a critical role in forming connections between neurons, according to a study in the August 18 issue of the Journal of Neuroscience.

A new wave of genetic tests for fragile X syndrome, the leading cause of inherited mental retardation and the most common genetic cause of autism, may make it possible to routinely screen pregnant women and newborns for the syndrome.

A drug that interferes with a biochemical pathway important in cancer can reverse some brain defects in mouse models of fragile X syndrome, according to a study published 11 August in the Journal of Neuroscience.

The amygdala, a brain region that regulates fear and anxiety, shows abnormal neuronal signaling in a mouse model of fragile X syndrome, according to two studies published this summer. These are the first to explore cellular defects in the region in fragile X.

Researchers have uncovered an important molecular piece of a learning mechanism that occurs at the junction between neurons. The findings, which may help understand how the brain is disrupted in disorders such as autism, appear in the 24 June issue of Neuron.

Children with fragile X syndrome show abnormal growth in several brain structures during the first few years of life, according to the first study to track how the disease unfolds in the brain during early development.

Several independent groups have found previously unknown risk genes for autism, schizophrenia and mental retardation. The candidate genes have one thing in common: they encode proteins that are needed for the healthy function of synapses, the junctions between neurons.