Inherited Variations in Noncoding Sections of DNA Associated with Autism

A new study has identified an association between paternally-inherited rare structural variants in noncoding segments of genes and the development of autism spectrum disorder (ASD). The study, funded in part by the National Institute of Mental Health (NIMH) and published in Science, adds to a growing body of research describing genetic contributors to ASD.

ASD is a developmental disorder that affects communication and behavior. While the exact causes of ASD are unknown, researchers have identified a number of genes associated with the development of ASD. Many studies have focused on examining the inheritance of, or mutations in, portions of genes that code for the creation of proteins or other molecular products. But these new findings suggest that rare, inherited structural differences in the noncoding portions of genes also contribute to ASD.

“Gene sequences represent only two percent of the genome.” said Jonathan Sebat, Ph.D., of University of California San Diego School of Medicine (UCSD) and the Beyster Center for Genomics of Psychiatric Diseases. “The next challenge is to identify ASD risk variants affecting genetic regulatory elements. Examining these elements will help us understand the genetic components that contribute to the development of ASD, and symptoms seen in people with ASD.”

Full story at NIMH

Amygdala neurons increase as children become adults — except in autism

In a striking new finding, researchers at the UC Davis MIND Institute found that typically-developing children gain more neurons in a region of the brain that governs social and emotional behavior, the amygdala, as they become adults. This phenomenon does not happen in people with autism spectrum disorder (ASD). Instead, children with ASD have too many neurons early on and then appear to lose those neurons as they become adults. The findings were published today in the journal Proceedings of the National Academy of Sciences (PNAS).

The amygdala is a small almond-shaped group of 13 regions (nuclei) that work as a danger detector in the brain to regulate anxiety and social interactions. Amygdala dysfunction has been linked to many psychiatric and neurodevelopmental disorders, including ASD, schizophrenia, bipolar disorder and depression.

“The amygdala is a unique brain structure in that it grows dramatically during adolescence, longer than other brain regions, as we become more socially and emotionally mature,” said Cynthia Schumann, associate professor in the Department of Psychiatry and Behavioral Sciences at the UC Davis MIND Institute and senior author of the paper. “Any deviation from this normal path of development can profoundly influence human behavior.” To understand what cellular factors underlie amygdala development, the team studied 52 postmortem human brains, both neurotypical and ASD, ranging from 2 to 48 years of age.

Full story at Science Daily

Suspect Molecules Overlap in Autism, Schizophrenia, Bipolar Disorder

Evidence has been mounting that some mental disorders share many of the same genetic risk factors. Now, researchers have discovered that this overlap extends to the molecular level – some of these suspect genes also turn on-and-off similarly in the brains of people with autism spectrum disorder (ASD), schizophrenia, and bipolar disorder. These molecular signatures may hold clues to what goes wrong in the brain in these disorders—and potentially ways to better treat or even prevent them.

In search of such clues, Drs. Daniel Geschwind and Michael Gandalof the University of California Los Angeles (UCLA), and colleagues, examined gene expression in postmortem brains of people who had been diagnosed with autism spectrum disorder (ASD), schizophrenia, bipolar disorder, major depressive disorder, or alcoholism. One of the largest such efforts of its kind to date, the study, funded by the National Institute of Mental Health (NIMH), tapped brain molecular data resources gathered through the NIMH-funded PsychENCODE consortium, a data-sharing collaboration among NIMH grantees.

Full story at NIMH

Suspect Molecules Overlap in Autism, Schizophrenia, Bipolar Disorder

Evidence has been mounting that some mental disorders share many of the same genetic risk factors. Now, researchers have discovered that this overlap extends to the molecular level – some of these suspect genes also turn on-and-off similarly in the brains of people with autism spectrum disorder (ASD), schizophrenia, and bipolar disorder. These molecular signatures may hold clues to what goes wrong in the brain in these disorders—and potentially ways to better treat or even prevent them.

In search of such clues, Drs. Daniel Geschwind and Michael Gandalof the University of California Los Angeles (UCLA), and colleagues, examined gene expression in postmortem brains of people who had been diagnosed with autism spectrum disorder (ASD), schizophrenia, bipolar disorder, major depressive disorder, or alcoholism. One of the largest such efforts of its kind to date, the study, funded by the National Institute of Mental Health (NIMH), tapped brain molecular data resources gathered through the NIMH-funded PsychENCODE consortium, a data-sharing collaboration among NIMH grantees.

Full story at NIMH

Common cerebral white matter abnormalities found in children with autistic traits

Structural abnormalities in the brain’s white matter match up consistently with the severity of autistic symptoms not only in children with autism spectrum disorder (ASD), but also, to some degree, in those with attention-deficit/hyperactivity disorder (ADHD) who also have autistic traits.

This is the finding of a new study, published September 6 in JAMA Psychiatry, which highlights evidence supporting the theory that common, underlying brain mechanisms may be responsible for autistic traits seen in both diagnoses.

Led by researchers in the Department of Child and Adolescent Psychiatry at NYU School of Medicine, the new study focused on white matter — nerve bundles that transmit information between brain regions. Researchers say the link between symptom severity and white matter structural patterns was most evident in the region of the brain called the corpus callosum, which connects the left and right cerebral hemispheres and enables communication between them.

Full story at Science Daily

Children with autism may be over-diagnosed with ADHD, new study suggests

A well-established screening tool used to assess children for attention-deficit hyperactivity disorder (ADHD) may be less accurate when a child has an autism spectrum disorder (ASD). Pediatric researchers report that children with ASD may mistakenly be diagnosed with ADHD because they have autism-related social impairments rather than problems with attention. This is important for understanding what are the right services and treatments for a child.

The study team, including one of the psychologists who developed the ADHD screening tool, concludes that the tool needs to be refined to better identify the correct disorder, and that clinicians should supplement the screening tool with careful clinical interviews.

Full story of autism over-diagnosed with ADHD at Science Daily

Percentage of US children who have chronic health conditions on the rise

The percentage of children with chronic health conditions is on the rise, and new research being presented at the Pediatric Academic Societies 2016 Meeting shows this is especially true among children who live in or near poverty.

Researchers presenting the study abstract, “National Trends in Prevalence and Co-morbid Chronic Conditions among Children with Asthma, Autism Spectrum Disorder, and Attention Deficit Hyperactivity Disorder,” looked at data from the National Survey of Children’s Health data for 2003, 2007, 2011 and 2012 to spot trends surrounding these conditions by sociodemographic characteristics in the United States.

The study found more significant increases in asthma and Attention Deficit Hyperactivity Disorder (ADHD) among children living in poverty, as compared to their wealthier counterparts. Poor children with these conditions also were more likely to have two or more additional diseases. Those living in extreme poverty who had asthma and ADHD, for example, were roughly twice as likely to have at least one other chronic medical condition. Some of the more common co-existing conditions included developmental delays, autism, depression or anxiety, behavioral or conduct issues, speech and language problems, epilepsy/seizure disorders and learning disabilities. Among children who had public health insurance, significant increases were seen among all the chronic diseases studied.

Full story of US children with chronic health conditions on the rise at Science Daily