Autism Science

Transcriptome Analysis Reveals Dysregulation of Innate Immune Response Genes and Neuronal Activity-Dependent Genes in Autism

Source: 
Nature
Date Published: 
December 10, 2014
Abstract: 

Using resources from the Autism BrainNet, a new study in brains affected by autism revealed a common factor of activated immune cells. Led by Dr. Dan Arking at Johns Hopkins, the project analyzed dats collected from 72 individuals, both with and without autism The findings compared gene expression across these two groups and from different brain banks. It also utilized a large dataset that contains data on existing autism risk genes. This represents the largest dataset so far in studying gene expression in the brains of autism. Previous studies have been too small to make meaningful conclusions, because of the lack of tissue available.

The team, which also included the University of Alabama at Birmingham, saw that in individuals with ASD, a type of immune cell called microglia was always active, with genes for inflammation always being turned on. Arking noted that he did not think that the inflammation itself as the root cause of autism, but that it is the marker of a downstream effect.

“This type of inflammation is not well understood but it highlights the lack of current understanding about how innate immunity controls neural circuits,” Dr. Andrew West, associated professor of neurology at the University of Alabama at Birmingham said.

Future of Autism Genetics Should Learn from its Past

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
December 9, 2014
Abstract: 

The results of sequencing studies are helping autism researchers narrow down what genes to look for and where. They can now put forth a statistically sound estimate of the overall genetic contribution of de novo mutations of different categories to autism. However, they still cannot pinpoint the causal mutations for many cases of autism because the genomic background noise remains high.

Snippets of RNA May Reverse Symptoms of Angelman Syndrome

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
December 4, 2014
Abstract: 

Small pieces of RNA restore the expression of a key gene missing in Angelman syndrome and offer the promise of a highly specific cure, researchers reported Monday in Nature. Injecting these RNA snippets into the brains of mice missing one copy of this gene, called UBE3A, reverses their memory problems.

Using Extended Pedigrees to Identify Novel Autism Apectrum Disorder (ASD) Candidate Genes

Source: 
Human Genetics
Date Published: 
November 29, 2014
Abstract: 

Copy number variations are known to play a role in autism spectrum disorders. In a novel approach to study CNVs that may be present in family members, scientists look at genes in multiple generations of families affected with or without ASD as well as other psychiatric disorders. In one family, a part of chromosome 11 jumped out as being important for autism and what is known as the ‘broader autism phenotype’. (This is when a person does not have a diagnosis but meets some of the criteria for ASD.) This region contains genes for mitochondrial function and detoxification, but was found in the only family where the specific mutation was passed on beyond just parent to child. This shows that the genetic risk factors are complex and not even the same within the same family.

Massive Sequencing Studies Reveal Key Autism Genes

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
October 29, 2014
Abstract: 

Analyzing the sequences of more than 20,000 people, researchers have unearthed the largest and most robust list of autism genes so far, they reported in the journal Nature.These 50 ‘high-confidence’ autism genes may help researchers understand the biological underpinnings of autism. The researchers found these genes by scouring the exomes, the protein-coding regions of the genome, looking for rare genetic glitches unique to people with autism.

Whole-Genome Sequencing Reveals New Types of Autism Risk

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
October 20, 2014
Abstract: 

Much of the genetic risk for autism may reside in regulatory regions of the genome, hidden from traditional methods of sequencing analysis. That's the upshot of preliminary results from three studies presented at the 2014 American Society of Human Genetics Annual Meeting in San Diego. Together, the findings from these new studies show the promise of looking for autism risk in unusual places.

Sex/Gender Differences and Autism: Setting the Scene for Future Research

Source: 
Journal of the American Academy of Child & Adolescent Psychiatry
Date Published: 
October 17, 2014
Abstract: 

A group in the UK conducted an exhaustive literature search surrounding current studies on sex and gender differences and autism spectrum disorders. This literature search grouped studies into four categories, focusing on behavioral features, diagnosis and disparity issues, causes of disparity, and developmental trajectory. These same topics will be discussed on October 29 at the Sex and Gender Differences in ASD science workshop in New York, sponsored by the Autism Science Foundation and Autism Speaks.

Siblings of Children with Autism can Show Signs at 18 Months

Source: 
Journal of the American Academy of Child & Adolescent Psychiatry
Date Published: 
October 14, 2014
Abstract: 

About 20% of younger siblings of children with Autism Spectrum Disorder (ASD) will develop the condition by age 3. A new study by Yale School of Medicine researchers has found that 57% of these younger siblings who later develop the condition already showed symptoms at age 18 months. Published in the October Journal of the American Academy of Child & Adolescent Psychiatry, this is the first large-scale, multi-site study aimed at identifying specific social-communicative behaviors that distinguish infants with ASD from their typically and atypically developing high-risk peers as early as 18 months of age.

New Mouse Model Mimics Brain Abnormalities in Autism

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
October 6, 2014.
Abstract: 

Mice with mutations in the autism-linked gene WDFY3 have enlarged brains reminiscent of those seen in some children with autism, finds a study published in Nature Communications. The brain overgrowth begins in the womb, the study found. WDFY3 plays a role in autophagy, a process that rids cells of damaged or unneeded parts. Mouse embryos with two copies of the mutant gene have enlarged brains and an excess of immature neurons that divide faster than usual. They also have misdirected patches of neurons. Similar changes have been observed in people with autism.

Method Reveals Thin Insulation on Neurons in Autism Brains

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
September 24, 2014
Abstract: 

There is less myelin in the brains of people with autism than in those of controls, according to a study published in Psychological Medicine. Myelin is an insulating material that allows neurons to fire rapidly. Researchers applied a method that measures myelin in living brains with autism for the first time. The researchers speculate that low myelin explains the weak connectivity observed in the brains of people with autism. Without proper insulation, electrical signals travel slowly along the axons, making it difficult for regions of the brain to coordinate their activity.