New protein synthesis is essential for long-lasting memory, and regulation of neuronal translation by the ERK and mTOR signaling pathways plays a crucial role in this process. Several monogenic syndromes associated with autism, notably fragile X syndrome and tuberous sclerosis complex (TSC), involve proteins that function in these translational regulatory pathways.

Autism spectrum disorders are a clinically heterogeneous group of disorders that share common features. Only an estimated 10 to 15 percent of autism cases are monogenic — caused by mutations in a single gene — but the molecular alterations in these disorders could reveal common pathogenic mechanisms shared across the spectrum.

Functional brain imaging studies of individuals with autism suggest that brain activity in response to sensory stimuli is delayed, multisensory brain responses are integrated over a longer time frame, and activity across brain regions is less synchronous than in typically developing people.

Betty Diamond and her colleagues at The Feinstein Institute for Medical Research in Long Island, New York, demonstrated the presence of antibodies that bind to brain tissue in the blood serum of approximately 10 percent of mothers of a child with autism spectrum disorder. More than half of these women also have anti-nuclear antibodies. Autoimmune disease is also more prevalent in these women than in the general population.

Mutations in certain genes that encode proteins at the synapse, the junctions between neurons, are known to be associated with autism spectrum disorders. Two such families of proteins, neurexins and neuroligins, are thought to be important for assembling synapses. However, the role of these molecules in synapse formation and overall neuronal function is still poorly understood.

There is currently no cure for any autism spectrum disorder, and the current pharmacological treatments have had limited success. Finding treatments for autism has proven challenging for two major reasons. First, defects in multiple genes increase risk for autism, which makes it difficult to study and identify effective treatments. Second, drug screening in neurons, which are non-dividing cells, poses immense technical challenges. Benjamin Philpot and his colleagues at the University of North Carolina have sought to overcome these challenges by developing a novel neuronal drug screen to identify small-molecule compounds for treating autism caused by dysregulation of a single gene, UBE3A.

The most common inherited form of autism is fragile X syndrome, which is caused by genetic inactivation of the fragile X mental retardation protein (FMRP). In addition to intellectual disability, children with this disorder exhibit extreme social anxiety, poor eye contact, repetitive behaviors, hand flapping and tactile avoidance — hallmark characteristics of people with autism.

Autism impairs the development of social behavior, emotions and communication. The prefrontal cortex plays an important role in the early development of these skills and displays abnormal growth and function in children with autism. Few studies have looked for autism-associated neural defects in this region in young children.

Children with autism and related disorders often have problems with language acquisition. Simon Fisher of Oxford University and his colleagues are aiming to uncover the neural mechanisms of abnormal language development by studying the key genetic pathways that can go awry in these disorders.

Luis Parada and his colleagues at the University of Texas Southwestern Medical Center in Dallas have been studying the brain morphology and behavior of mice with mutations that are specific to certain brain regions. In previous work, they generated a mouse line in which PTEN was deleted in neurons of the cortex and hippocampus.