In an effort to pin point where exactly it all begins, scientists have identified a so called ‘molecular switch’ to the thousand or more genes that have been associated with autism. Of these genes, which are the ones that are directly responsible for autism remains to be determined. A team of scientists from the University of North Carolina Health Care System has been able to show a genetic mutation that renders the molecular switch dysfunctional, leading to autism.
The study was published this week in the prestigious journal Cell. The team of researchers led by Mark Zylka identified that the key lies in manipulating the enzyme UBE3A. The scientists found that simply by adding a phosphate molecule into the enzyme, its actions could be turned on and off. They found that a mutation associated with autism destroys this vital regulatory switch. Being destroyed, this enzyme cannot then be turned off and becomes hyperactive, driving abnormal brain development on the path to autism. The study was conducted in mice as well as human cell lines, and it was found that typical parents could give birth to children with a mutated enzyme leading to autism in the kid.
Journal Reference: Jason J. Yi, Janet Berrios, Jason M. Newbern, William D. Snider, Benjamin D. Philpot, Klaus M. Hahn, Mark J. Zylka. An Autism-Linked Mutation Disables Phosphorylation Control of UBE3A. Cell, 2015; DOI: 10.1016/j.cell.2015.06.045
Loss of critical brain receptor common link between autism and schizophrenia
A team of scientists from the prestigious Salk Institute have identified how loss of a key receptor in the brain cells, neurons, leans to anti-social and compulsive behaviors. The team led by Terrence Sejnowski published the findings this week in the journal Molecular Psychiatry. The team found that receptor called mGluR5 played a vital role in cognition and generation of certain wave patterns in the brain. On deletion of this receptor from the parvalbumin-positive interneurons of the brain, the mice developed behaviors similar to schizophrenia and autism. The mice developed repetitive grooming behaviors, and obsessive tendencies.
Earlier studies have proven that when signaling was disrupted right at the molecular level in these interneurons, the neuronal networks didn’t develop the way they should. The mGluR5 receptors have been linked to Fragile X Syndrome as well as addiction and anxiety disorders in the past. Yet, this role in the inhibitory interneurons was hitherto unknown.
The discovery adds weight to the thought chain that autism might be produced by changes that take place in the brain after birth, and not just before birth.
Journal Reference: S A Barnes, A Pinto-Duarte, A Kappe, A Zembrzycki, A Metzler, E A Mukamel, J Lucero, X Wang, T J Sejnowski, A Markou, M M Behrens. Disruption of mGluR5 in parvalbumin-positive interneurons induces core features of neurodevelopmental disorders. Molecular Psychiatry, 2015; DOI: 10.1038/mp.2015.113
Understanding idioms, the autism way
Norwegian University of Science and Technology scientists decided to examine the link between perception and language in people with autism across disciplines to understand how language and perceptions evolve over time with learning. This information could help create better learning interventions for kids with autism. The study was led by Mila Vulchanova and is part of the LanPercept program.
Studies have shown that kids on the spectrum might have very high IQs and might be great with grammar, even better than typical kids same age, yet tend to struggle with communication. This is because they tend to understand language literally, making idioms very difficult to understand. The study found that the participants tended to take the idioms literally over 50% of the time.
The authors concluded that hopefully the study would help in improving linguistic profiles for children on the spectrum and develop smarter ways to help them teach language that can improve social communications.