2012

Genetics: X chromosome disorder linked to autism
Duplication of a region on the X chromosome leads to a genetic disorder characterized by severe autism, according to a study published 25 November in Annals of Neurology.
Cognition and behavior: Asperger brains similar across sexes
The brains of men and women with Asperger syndrome are more similar than are those of male and female controls, according to a study published in the January issue of the American Journal of Neuroradiology. The results lend support to the 'extreme male brain' theory of autism, the researchers say.
Clinical research: Mice model Rett syndrome’s heart symptoms
Mice engineered to carry a Rett syndrome mutation only in neurons are prone to an irregular heartbeat that can lead to sudden death, according to a study published 14 December in Science Translational Medicine.
Molecular mechanisms: DISC1 variants inhibit neurogenesis
Three variants of DISC1, a gene implicated in schizophrenia and autism, may disrupt the formation of new neurons in the brain, according to a study published 17 November in Neuron.
Clinical research: Study suggests drug for fragile X syndrome
A compound that boosts inhibitory signals in the brain could treat hyperactivity and excitability in mice that model fragile X syndrome, according to a study published 8 November in Developmental Neuroscience.
Genetics: X chromosome gene linked to autism in males
TBL1X, a gene located on the X chromosome, is associated with autism in males but not in females, according to a study published 3 November in Molecular Autism.
Cognition and behavior: Blinking measures social interest
Toddlers with autism do not anticipate emotional moments in videos of social scenes, unlike controls, according to a study published 27 December in the Proceedings of the National Academy of Sciences. 
Molecular mechanisms: Autism gene tied to neuronal junctions
Neurobeachin, or NBEA, an autism–associated gene, may regulate the transport of signaling molecules to neuronal branches, according to a study published 22 November in Nature Communications.
Clinical research: Prozac may help adults with autism
Fluoxetine, an antidepressant marketed as Prozac, may alleviate repetitive behaviors in adults with autism, according to a study published 2 December in the American Journal of Psychiatry.
Genetics: New dataset confirms schizophrenia associations
A new study uses data from more than 10,000 typical individuals to validate candidate regions implicated in schizophrenia.
Cognition and behavior: Brain scans yield few signs of autism
The results of two new studies support recommendations against the use of brain scans to diagnose autism.
Clinical research: Two compounds treat Rett syndrome in mice
Two compounds that enhance the activity of BDNF, a protein needed for the growth of neurons, improve motor skills in mouse models of Rett syndrome and increase the mice’s lifespan.
Molecular mechanisms: Lithium treats fragile X in mice
Lithium alleviates the symptoms of fragile X syndrome in mice in part by normalizing protein synthesis in the brain, according to a study published 29 December in Neurobiology of Disease.
Cognition and behavior: Mouse models human Rett mutation
A mouse model of Rett syndrome that mimics a mutation seen in people shows many features of the disorder, such as hand clasping, according to a study published 27 November in Nature Neuroscience.
Molecular mechanisms: Alzheimer’s protein linked to fragile X
Lowering the levels of a protein associated with Alzheimer’s disease can rescue symptoms of fragile X syndrome in mice, according to a study published 26 October in PLoS One.
Clinical research: Twin study links low birth weight to autism
When twins differ in their diagnosis of autism, the twin with the lower birth weight is about three times more likely to develop the disorder than his or her sibling, according to a study published in the December issue of Psychological Medicine.
Genetics: Large variants linked to intellectual disability
Intellectual disability is more likely to be associated with multiple, large or non-inherited duplications and deletions of DNA than is autism, according to a study published 7 November in PLoS Genetics.
Clinical research: Autism threshold higher in girls than boys
Girls may have a higher threshold for the genetic abnormalities that lead to autism than boys do, according to a new study in the January issue of the American Journal of Medical Genetics Part B.  
Molecular mechanisms: Extra MeCP2 leads to anxiety in mice
Two genes may be responsible for autism symptoms in mice with extra copies of the Rett syndrome gene, according to a study published 8 January in Nature Genetics.
Genetics: Autism, Tourette syndrome genes overlap
Genes implicated in Tourette syndrome overlap with those involved in autism, according to an analysis of rare DNA duplications and deletions in people with the disorder, published in the March issue of Biological Psychiatry.
Cognition and behavior: MEG detects sound sensitivity
Brain imaging can detect acute sensitivity to sound in individuals with autism, according to a study published 25 January in Neurophysiology.
Clinical research: Rates of autism rise based on birth year
The likelihood of being diagnosed with autism has increased for children born each year since 1992, especially for individuals at the higher-functioning end of the autism spectrum, reports a study published 7 December in The International Journal of Epidemiology.
Molecular mechanisms: Study reveals new fragile X drug target
Researchers have identified a new mechanism that may underlie a runaway cell signaling pathway in fragile X syndrome. The results were published 22 January in Nature Neuroscience.  
Genetics: Different mutations lead to autism in same family
Twin brothers who have autism carry a non-inherited duplication that overlaps with 16p11.2, a chromosomal region that has been associated with autism. Their brother, who also has autism, has a nearby deletion within 16p11.2, according to a study published 11 January in the European Journal of Human Genetics.
Cognition and behavior: Contaminant acts with autism gene
A commonly used flame retardant may lead to deficits in sociability, learning and memory in healthy female mice and those that model Rett syndrome, according to a study published 15 February in Human Molecular Genetics. The effects are different in Rett syndrome models compared with healthy mice, suggesting gene-environment interactions.
Clinical research: Autism genes linked to autoimmune disease
The genetic risk factors for autism may also increase a person’s risk of developing ankylosing spondylitis, a form of arthritis of the spine, and decrease the risk of multiple sclerosis, according to a study published 13 December in Translational Psychiatry.
Molecular mechanisms: Protein synthesis boosted in fragile X
A cellular pathway that initiates protein synthesis may be overactive in individuals with fragile X syndrome, according a study published 23 January in Genes, Brain and Behavior.
Genetics: Maternal and paternal age increase risk of autism
The odds of having a child with autism begin to rise at age 35 for both men and women, but that risk does not increase further when both parents are over 35, according to a large study published in the March issue of Annals of Epidemiology.
Cognition and behavior: Study probes speech processing
Children with autism activate more brain regions than controls do when listening to tonal inflections in speech that convey meaning. The findings were published 19 December in Child Neuropsychology.
Clinical research: Gut bacteria prevalent in autism
A certain type of bacteria is prevalent in the intestines of children who have both autism and gastrointestinal (GI) symptoms but absent in controls, according to a study published 10 January in mBio.
Molecular mechanisms: Autism protein forms aggregates
DISC1, an autism-associated protein, can form large aggregates that deplete the amount of functional DISC1 in cells, according to a study published 14 February in Human Molecular Genetics.
Genetics: Autism linked to two mutations in same gene
Two mutations in an autism-associated gene, neurexin-1, may have combined to cause autism in one man, whereas family members with only one of the two mutations have other neurological disorders, according to a study published 15 February in the American Journal of Medical Genetics Part B.
Cognition and behavior: Brain changes tied to autism severity
Adults with autism have regional differences in brain volume in areas that play a role in social behavior and communication compared with controls, according to a large study published in the February issue of Archives of General Psychiatry. The differences correlate with the severity of autism symptoms, the study also shows.
Clinical research: Joint attention can predict autism outcome
How easy it is to engage the attention of a child with autism by gazing or pointing at an object may predict how well he or she will be able to function as an adult, according to a study published in the February issue of the Journal of Autism and Developmental Disorders.
Molecular mechanisms: Maternal infection linked to autism
Molecules generated by an immune reaction in pregnant mice affect the brains of their offspring, leading to changes in gene expression, according to a study published 30 January in Brain, Behavior and Immunity.
Genetics: Autism risk higher in full than in half siblings
Full siblings are twice as likely as half siblings to share a diagnosis of autism, according to a short report published 28 February in Molecular Psychiatry. The results suggest that genetic factors play an important role in the risk of developing autism, the researchers say.
Cognition and behavior: Mirror neurons age normally in autism
Age-related changes to the mirror neuron system — a pathway thought to be involved in empathy — are no different in individuals with autism compared with controls, according to a meta-analysis published 1 February in Social Cognitive and Affective Neuroscience. The results challenge previous reports that suggest deficits in the mirror neuron system diminish with age in individuals with autism.
Clinical research: Signs of autism emerge in infancy
Warning signs of autism, such as deficits in social ability and fine motor skills, are apparent as early as 6 months of age, according to a large longitudinal study published in the March issue of the Journal of the American Academy of Child and Adolescent Psychiatry.
Molecular mechanisms: Extra MeCP2 affects brain signaling
Mice with an extra copy of MeCP2, the Rett syndrome gene, have impaired signaling between neurons in the hippocampus, a brain region that plays an important role in memory, according to a study published 29 February in The Journal of Neuroscience.
Genetics: Rare, common autism variants may function together
Researchers have mapped networks of genes expressed at the same time and place in the brain and shown that rare and common autism-linked mutations are likely to function in the same pathways. The results were published 8 March in PLoS Genetics.
Cognition and behavior: Corpus callosum smaller in autism
Children with autism have a smaller corpus callosum, a bundle of nerve fibers that connects the two hemispheres of the brain, compared with controls, and this difference persists over two years of development, according to a study published 18 February in the Journal of Autism and Developmental Disorders.
Clinical research: Gestation period affects autism symptoms
Both premature and post-term babies develop more severe symptoms of autism than those born close to their due dates, according to a study published 16 March in the Journal of Autism and Developmental Disorders.
Molecular mechanisms: Autism gene modulates connectivity
Neurons lacking PTEN, an autism-associated gene also involved in cancer, are hyperconnected to both near and distant brain cells, according to a study published 1 February in The Journal of Neuroscience.
Genetics: Language gene may regulate autism, schizophrenia
FOXP2, a protein linked to language development that regulates the expression of some autism-associated genes, also dampens expression of DISC1, mutations in which have been linked to both schizophrenia and autism. The results were published 20 March in Human Molecular Genetics.
Cognition and behavior: Language defect identified in autism
Children who have both autism and intellectual disability may understand fewer words than their speaking skills suggest, which is not the case for typically developing children or those with intellectual disability alone. The results were published 21 February in the Journal of Autism and Developmental Disorders.
Clinical research: Drug improves quality of life with autism
Aripiprazole, a drug approved by the U.S. Food and Drug Administration to treat irritability in children with autism, may also improve their overall health-related quality of life, according to a retrospective analysis of two clinical trials. The results were published 21 March in Clinical Therapeutics.
Molecular mechanisms: Serotonin regulation linked to autism
An autism-associated variant in a gene that regulates the chemical messenger serotonin leads to abnormal serotonin regulation and autism-like behaviors in mice. The results were published 3 April in the Proceedings of the National Academy of Sciences.
Cognition and behavior: Reward circuit abnormal in autism
The reward center of the brain is less active in children with autism compared with controls in response both to praise and monetary rewards, according to a study published 11 April in Social Cognitive and Affective Neuroscience.
Clinical research: Study suggests four autism subgroups
Individuals with autism may belong to one of four groups with discrete sets of symptoms, the most distinct of which includes immune system abnormalities accompanied by sleep problems and sensory sensitivity. The results were published in the April issue of Autism Research.
Molecular mechanisms: Stress pathway dysregulated in autism
Two studies report abnormalities in the system that mediates the body’s response to stress in two mouse models of autism-related diseases: Angelman syndrome and Rett syndrome. The results were published in the April issue of Human Molecular Genetics.
Cognition and behavior: Autism, antisocial brains differ
Autism and antisocial disorder are separate conditions, with distinct differences in underlying brain structure, according to a neuroimaging study of the general population. The results were published 4 April in The Journal of Neuroscience.
Genetics: Study further implicates rare CNVs in autism
Individuals with autism are more likely than controls to have small, rare duplications or deletions of stretches of DNA in genes that play a role in dampening signals in the brain, according to a study published 2 April in Molecular Autism.
Clinical research: Autism development follows distinct paths
A fraction of children with autism show significant improvements in social and communication skills over time compared with their peers with the disorder, according to a study published 2 April in Pediatrics.
Molecular mechanisms: Growth factor altered in autism brains
The brains of individuals with autism have higher-than-typical levels of the precursor to a neuronal growth factor called BDNF, according to a study published in the April issue of the Journal of Neuropathology and Experimental Neurology. The results suggest a mechanism for altered brain development in autism.
Cognition and behavior: Drug improves memory in autism
Propranolol, a drug used to treat heart disease and anxiety, might improve memory and attention deficits in autism, according to a study published in the May issue of the Journal of the International Neuropsychological Society.
Genetics: SHANK1 mutations found in men with autism
Researchers have identified deletions in SHANK1 — the third member of a gene family that is closely linked to autism — in five men with the disorder, they reported 4 May in the American Journal of Human Genetics. This is the first study linking SHANK1 mutations to people with autism.
Cognition and behavior: Language links differ in autism brains
The bundles of nerve fibers that connect two regions important for language are abnormal in the brains of children with autism, according to a study published 5 April in the American Journal of Neuroradiology.
Molecular mechanisms: SHANK2, SHANK3 mouse brains differ
Mice lacking the autism-associated gene SHANK2 show autism-like behaviors similar to those seen in mice lacking SHANK3, another member of the same gene family. But SHANK2 and SHANK3 mice have distinct alterations at neuronal junctions, according to a report published 29 April in Nature.
Clinical research: Early interventions improve language
Toddlers with autism who receive behavioral interventions that improve joint attention — engaging and following others’ focus — have better language ability five years later than do controls, according to a study published in May in the Journal of the American Academy of Child and Adolescent Psychiatry.