Today in the News (16 Aug 09)

Evolution:
The Peopling Of The Americas: Genetic Ancestry Influences Health, Anthropologist Says. At one time or another most of us wonder where we came from, where our parents or grandparents and their parents came from. Did our ancestors come from Europe or Asia? As curious as we are about our ancestors, for practical purposes, we need to think about the ancestry of our genes, according to Cecil Lewis, assistant professor of anthropology at the University of Oklahoma. Lewis says our genetic ancestry influences the genetic traits that predispose us to risk or resistance to disease. Lewis studies genetic variation in populations to learn about the peopling of the Americas, but his studies also have an impact on genetic-related disease research. Some 15,000-18,000 years ago, people came from Asia through the Bering Strait and began to fill the American continents. The Americas were the last continents to be populated, so Lewis wants to understand how this process happened. His recent study focuses on South America and asks what part of the subcontinent has the most genetic diversity.

Speciation Through Genome Duplication More Common In Plant Evolution Than Previously Thought. Extra genomes appear, on average, to offer no benefit or disadvantage to plants, but still play a key role in the origin of new species, say scientists from Indiana University Bloomington and three other institutions in this week's Proceedings of the National Academy of Sciences. Plant biologists have long suspected polyploidy -- the heritable acquisition of extra chromosome sets -- was a gateway to speciation. But the consensus was that polyploidy is a minor force, a mere anomaly that accounts for 3 or 4 percent of the world's flowers and ferns. The first direct, comprehensive survey of polyploid speciation in plant evolution severely challenges that notion.

Autism:
Imitation Promotes Social Bonding In Primates. Imitation, the old saying goes, is the sincerest form of flattery. It also appears to be an ancient interpersonal mechanism that promotes social bonding and, presumably, sets the stage for relative strangers to coalesce into groups of friends, according to a study by a team of scientists at the National Institutes of Health and two Italian research institutions. The study authors found that capuchin monkeys preferred the company of researchers who imitated them to that of researchers who did not imitate them. The monkeys not only spent more time with their imitators, but also preferred to engage in a simple task with them even when provided with the option of performing the same task with a non-imitator. "Researchers have known that human beings prefer the behavior of other people who subtly imitate their gestures and other affects," said Duane Alexander, M.D., Director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, where the NIH portion of the study was conducted. "Observing how imitation promotes bonding in primates may lead to insights in disorders in which imitation and bonding is impaired, such as certain forms of autism."

Antibodies To Strep Throat Bacteria Linked To Obsessive Compulsive Disorder In Mice. A new study by researchers at Columbia University Mailman School of Public Health's Center for Infection and Immunity indicates that pediatric obsessive-compulsive disorder (OCD), Tourette syndrome and/or tic disorder may develop from an inappropriate immune response to the bacteria causing common throat infections. The mouse model findings, published online by Nature Publishing Group in this week's Molecular Psychiatry, support the view that this condition is a distinct disorder, and represent a key advance in tracing the path leading from an ordinary infection in childhood to the surfacing of a psychiatric syndrome. The research provides new insights into identifying children at risk for autoimmune brain disorders and suggests potential avenues for treatment.

Vaccines:
News from Dr. Plait on the anti-vax pro-disease nutters: The Australian skeptics are still hammering away at Meryl Dorey, the Australian Vaccination Network, and their (to be charitable) distortions of the truth. It’s nice to see.

And what we have seen is that, like a pinata when that critical blow is made, a torrent of dumbosity comes out.

Which brings up an interesting point. A lot of people think that using an ad hominem — an argument that attacks the person and not the issue –is a logical fallacy. That’s not necessarily the case. For example, if someone on the street walks up to me and say, "Aliens speaking with the voice of Glenn Beck are sitting on my shoulders and forcing me to eat brussel sprouts, and Obama’s health care plan will set up death panels," then there is some merit in questioning the person’s sanity before wondering if what they say about the health care plan is true.

So if you’re inclined to give Meryl Dorey and her AVN group the benefit of the doubt, you might want to read up on some of the other, um, stuff they believe. It may open your eyes.

I wonder what the anti-vax pro-disease nutters will make of this? Needle-free, inhalant powder measles vaccine could save thousands of lives. The first dry powder inhalable vaccine for measles is moving toward clinical trials next year in India, where the disease still sickens millions of infants and children and kills almost 200,000 annually, according to a report presented here today at the 238th National Meeting of the American Chemical Society (ACS). Robert Sievers, Ph.D., who leads the team that developed the dry-powder vaccine, said it's a perfect fit for use in back-roads areas of developing countries. Those areas often lack the electricity for refrigeration, clean water and sterile needles needed to administer traditional liquid vaccines.