Neuroscience

Researchers are saying a new analysis of data on the genetics of autism spectrum disorder disputes a commonly held belief that autism results from the chance combinations of commonly occurring gene mutations, which are otherwise harmless. 

They find, instead, further evidence to suggest that devastating "ultra-rare" mutations of genes that they classify as "vulnerable" play a causal role in roughly half of all autism spectrum disorder cases. The vulnerable genes to which they refer harbor what they call an LGD, or likely gene-disruption. These LGD mutations can occur "spontaneously" between generations, and when that happens they are found in the affected child but not found in either parent. 

Scientists at Karolinska Institutet and Karolinska University Hospital in Sweden have discovered a new explanation for severe early infant epilepsy. Mutations in the gene encoding the protein KCC2 can cause the disease, hereby confirming an earlier theory. The findings are being published in the journal Nature Communications.

Girls with autism display less repetitive and restricted behavior than boys do, according to a study by researchers at the Stanford University School of Medicine.

The study also found that brain differences between boys and girls with autism help explain this discrepancy.

The study, which will be published online Sept. 3 in Molecular Autism, gives the best evidence to date that boys and girls exhibit the developmental disorder differently.

Scientists have pinpointed a population of neurons in the brain that influences whether one drink leads to two, which could ultimately lead to a cure for alcoholism and other addictions.

A new study finds that alcohol consumption alters the structure and function of neurons in the dorsomedial striatum, a part of the brain known to be important in goal-driven behaviors. The findings could be an important step toward creation of a drug to combat alcoholism. 

"Alcoholism is a very common disease," said Jun Wang, M.D., Ph.D., the lead author on the paper and an assistant professor in the Department of Neuroscience and Experimental Therapeutics at the Texas A&M College of Medicine, "but the mechanism is not understood very well."

Male teens who experiment with cannabis before age 16, and have a high genetic risk for schizophrenia, show a different brain development trajectory than low risk peers who use cannabis.

The discovery, made from a combined analysis of over 1,500 youth, contributes to a growing body of evidence implicating cannabis use in adolescence and schizophrenia later in life. 


Repetitive transcranial magnetic stimulation can help alleviate symptoms of autism, such as anxiety. AGUILA_JONATHAN/Flickr, CC BY-NC-ND

By Peter Enticott, Deakin University


Want more working memory? Then you need to expand your brain. Credit: Flickr/Elena Gatti, CC BY

By Joel Pearson

Before we had mobile phones, people had to use their own memory to store long phone numbers (or write them down). But getting those numbers into long-term memory could be a real pain.

A collaboration between more than 70 researchers across the globe has uncovered nine new genes on the X chromosome that, when knocked-out, lead to learning disabilities. The international team studied almost all X chromosome genes in 208 families with learning disabilities - the largest screen of this type ever reported. 

Population studies indicate that up to 90 percent of cases of autism and what are referred to as autism spectrum disorders have some genetic component, but only 10 percent of cases can be attributed to known genetic and chromosomal syndromes.

Since several of those conditions involve deletions or duplications of chromosomal segments – including an inherited deletion of a region of chromosome 15 – investigators have conducted a complete genome scan of samples from the Autism Genome Research Exchange, which contains DNA from families in which at least one child has autism or a related disorder.


There's no one universal 'intelligence gene' but many thousands each contributing a small increment – and here are three.Credit: Andrew Huff/Flickr (cropped), CC BY

By Beben Benyamin, The University of Queensland and Peter Visscher, The University of Queensland