Our bodies are picky eaters when it comes to amino acids, and sometimes just a small screw-up can cause larger problems down the road. Scientists recently found an association between an amino-acid depleting mutation, and neurological problems in a small sample of humans. In mice with the same mutation, nutritional supplements reversed similar symptoms, offering the possibility of a treatment for the human disorder in the future. The results appeared in the journal Science. Read More
Children of older mothers, scientists have long known, are at higher risk for certain genetic disorders such as Down syndrome. But the father’s age is matters, too. As a father’s age increases, research shows, so does his child’s risk of mental illness, schizophrenia and autism in particular. In Scientific American, Nicole Grey explores the link between a father’s age and his child’s health, as well as the tricky questions about what mechanisms are behind the that link: genes, epigenetic changes, environment, or some combination of the three.
What’s the News: A number of recent studies have suggested that brain scans could be used to diagnose autism. Virginia Hughes investigated these claims in a report for the Simons Foundation Autism Research Initiative. While some researchers feel these tests could soon be ready for the clinic, she found, others feel that relying on the scans for diagnosis is at least premature, and perhaps entirely misguided. Some important points in her report:
How the Would-Be Autism Tests Work:
More than a dozen years have passed since the 1998 study in The Lancet in which researcher Andrew Wakefield argued his case that vaccines are the cause of autism. We here at DISCOVER have long considered his claims to be dubious and damaging to public health, but in the last few years the edifice upon which the anti-vaccination movement was built has been falling down. In 2004 most of the coauthors on the Wakefield study retracted the interpretation section of the paper, and early last year The Lancet officially retracted the entire paper. Now, this week, the British Medical Journal’s investigation calls Wakefield an out-and-out “fraud.”
Of course, the word “fraud” implies intent; when writing about Wakefield I had my suspicions, but always wrote as if he were just wrong, and not deliberately lying to vulnerable parents.
But deliberate fraud is what he’s now accused of. Brian Deer, an investigative journalist, has written a multi-part series on the BMJ site which slams Wakefield. Fiona Godlee, BMJ’s editor-in-chief, also writes about this… and just to be clear, she uses the word “fraud” nine times in her editorial.
Brian Deer’s article on BMJ is nothing short of a tour-de-force, and is a horrifying tale of how Wakefield allegedly falsified medical research deliberately while operating under a huge conflict of interest. Deer’s article is meticulously referenced and footnoted… but still, I know this won’t stop the antivaxxers.
Read the rest of Phil’s post about this at Bad Astronomy.
Bad Astronomy: And now, the antivax failure is complete: The Lancet withdraws Wakefield’s paper
DISCOVER: Vaccine Phobia Becomes a Public Health Threat
DISCOVER: Why Does the Vaccine/Autism Controversy Live On?
Autism researchers already knew that a variant of gene called CNTNAP2 that appears in about one-third of people is associated with higher risk for developing the condition. A study this week out in Science Translational Medicine puts that genetic marker together with what it appears to do in the brain: cause too many connections inside the frontal lobe of the brain, but too few from there to other brain regions. That could be a key clue in unraveling the learning and language difficulties that frequently appear in autism spectrum disorders.
The gene produces a protein called CASPR1 and is active during brain development — mostly during frontal-lobe development. “During early development, it is localized to parts of brain that are ‘more evolved’ — areas where learning and language happen, the frontal lobes where really complex thinking takes place,” says Ashlee Scott-van Zeeland, a postdoctoral fellow at the Scripps Translational Science Institute in La Jolla, Calif., and lead author of the study. “[It is] thought to help structure the brain.” [TIME]
To study its effects, Scott-Van Zeeland and company studied 32 kids between 11 and 13 in age. Some were autistic, some not, and many of the non-autistic kids carried the CNTNAP2 gene variant. The scientists examined the children’s brains through fMRI while the kids played a game intended to stimulate brain regions that the gene affects.
Your pencil marks on the door frame mark your kids’ ascending height; your photo albums carry the visual record of their ascending ages. Scientists have figured out a new way to track growing up: studying the normal evolution of connections between parts of the brain as a person ages toward adulthood. If advanced far enough, such a method could even help to catch developmental disability.
In a study out this week in Science, the team led by Nico Dosenbach outline the technique based on functional connectivity MRI, or fcMRI. Where the MRI scans we cover more frequently typically reveal brain structure or activity in a particular region, fcMRI focuses on the connections across the brain.
The research team scanned the brains … of 238 normally developing subjects aged 7 to 30, for five minutes. By comparing 200 of 12,720 key functional brain connections and assessing them through multivariate pattern analysis, researchers then predicted volunteer subjects’ developmental status. [Scientific American]
Researchers have published the largest-existing study on the genetic causes of autism, comparing 996 autistic individuals to 1,287 people without the condition. Their results, which appear today in Nature, may provide unexplored avenues for treatment research, but also show in new detail the disorder’s sheer genetic complexity. For example, they have found “private mutations” not shared between people with autism and not inherited from their parents.
According to The Centers for Disease Control and Prevention, one in 110 children in the United States has autism spectrum disorder, and that the prevalence of autism among eight-year-olds has increased 57 percent from 2002 to 2006. There is no known cure, although intensive behavioral therapy helps some kids.
Hilary Coon, Ph.D., a lead author on the study and research professor of psychiatry at the University of Utah School of Medicine, said while research shows scientists are making progress in understanding the causes of autism, it is increasingly clear that autism is a multifaceted disorder with both genetic and environmental causes. “We are whittling away at it,” Coon said. “But a brain-related disorder, such as autism, is amazingly complex. It’s not really one entity.” [University of Utah press release]
For this study, researchers at the international Autism Genome Project wanted a closer, more detailed picture of the over 100 genes commonly linked to autism. They looked for rare variants–small deletions or additions to the DNA sequences that make up these genes. They found that people with autism had a higher number of these variants than those without the disorder, and that some of these DNA differences were not inherited. That means these DNA changes occurred either in the egg cell, sperm, or in the developing embryo.
For the first time, researchers have found that oxytocin–the hormone at work when breastfeeding mothers bond with their babies and when couples cuddle–can help autistic patients with social interactions. The small but pioneering study showed that when autistic adults inhaled the “love hormone” oxytocin though a nasal spray, they paid more attention to expressions when looking at pictures of faces and were more likely to understand social cues in a game simulation [Reuters].
The findings will be published this week in the journal Proceedings of the National Academy of Sciences. Although more research is needed to confirm and explore the findings, the results are the latest in a growing body of evidence indicating that the hormone could lead to ways to help people with the often devastating brain disorder function better [Washington Post].
People with autism or with high-functioning autism spectrum disorders like Asperger’s syndrome have difficulty engaging in social situations [Scientific American]. They normally have trouble making eye contact and are awkward around other people. They also suffer from low levels of oxytocin–a hormone that is found naturally in humans and animals and helps humans understand emotions and social cues better.