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Mental illness 'in the genes'
A study indicates that people with a rare version of Prader Willi syndrome (PWS) are susceptible to mental illness. The condition is caused by the loss of a small part of chromosome 15 inherited from the father, or - in the rarer form - by inheriting two copies of the mother's chromosome 15.
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news.bbc.co.uk
'Pain gene' found
Scientists have found a gene whose absence can help reduce pain. Tests on genetically engineered mice which lacked a particular gene showed a "dramatic" loss of sensitivity, appearing to feel up to 50% less pain compared to mice who had the gene.
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news.bbc.co.uk
Geron Settles Suit on Embryo Stem Use
Geron Corp. said it confirmed its right to use stem cells derived from human embryos for some commercial products, settling a lawsuit filed by a university foundation.
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The Los Angeles Times
Schizophrenia
The portrayal of paranoid schizophrenia in the film A Beautiful Mind is creating controversy. Is it possible, as the film posits, that a person afflicted with this illness can keep it under control through sheer willpower? Is there a connection between mental illness and genius?
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cgi1.usatoday.com
Piecing Together Polynesia's Past
Tongatapu, Mr. Burley concluded, "probably served as the initial staging point for population expansion" to other islands of Tonga and into Samoa. The place seemed to be what anthropologists and geneticists call a founding colony. These people, he said, must have "formed the gene pool for all the rest of Polynesia."
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From this new frontier, scholars think, the ancient navigators perfected the double-hull outrigger sailing canoe and set out on their final expansion. Each of their bigger canoes probably carried tens of people with their pigs and cargo.
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The seafarers made it all the way east to Tahiti and northeast to Hawaii. Hawaii is separated from Samoa and Tonga by more than 2,500 miles (4,000 kilometers), and from Tahiti by 2,700 miles. Then they ranged south to New Zealand and farther east to Easter Island. The whole of Polynesia, extending over almost one-fourth of the Pacific, thus became the last large area of the world to be settled by people.
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The pottery by the lagoon, which was excavated in 1999, held clues to where the seafarers who reached Tongatapu had originated. In an analysis of bits of the shards, William Dickinson, a University of Arizona geologist, found sandy minerals exotic to Tonga. Some of the pots had been brought there from elsewhere. Further study revealed that the artifacts were composed of minerals found only on the Santa Cruz Islands in Melanesia, 1,200 miles to the west and closer to New Guinea and Australia.
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In a report recently in The Proceedings of the National Academy of Sciences, Mr. Burley and Mr. Dickinson called the shards the first physical evidence that linked the voyages of the Lapita people between the western and eastern regions of the wide Pacific. This further established their capability for "geographically extensive inter-island voyaging from or through island groups well to the west of Tonga during the earliest human presence in Polynesia."
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The researchers also wrote that the "ties back to the Santa Cruz Islands may imply that Tonga was initially settled by voyagers traveling directly from central Melanesia, rather than through intermediate settlements in Fiji, as has commonly been assumed."
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Other scholars of Pacific prehistory said, however, that the new research left unresolved many of the fundamental questions of Polynesian origins. Who were the people that produced the Lapita pottery and distinctive stone tools, beads, rings and shell ornaments? Were they an ethnically distinct society of newcomers, or one with diverse groups sharing a handicraft style? What was the relationship of the Lapita culture to descendants of the first settlers of the Pacific, beginning 45,000 years ago, who occupied Australia, New Guinea and nearby islands?
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Although hypotheses abound, no consensus answers have emerged. "We really don't have a good common-sense picture or story of what the migrations were really like," said John Edward Terrell, an anthropologist at the Field Museum of Natural History in Chicago.
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The first of the ornate pots with geometric designs were excavated in 1952 and called Lapita after the discovery site in the Melanesian island of New Caledonia. Subsequent exploration has uncovered the earliest known Lapita artifacts, about 3,500 years old, in the Bismarck Archipelago, northeast of New Guinea. The trail of shards leads from there east to Polynesia. But did the art of making Lapita pottery originate with the indigenous Melanesian population there, or was it introduced by new arrivals?
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This so-called "Polynesian problem" may be more than academic. Newly independent nations in the Pacific, anthropologists noted, are expected to look to history and archaeology in creating distinctive postcolonial cultures.
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Early European explorers seem to have been the first to speculate about the identity of the Pacific islanders. In the 18th century, Captain James Cook was struck by the resemblance of the customs and appearance among the light-skinned Polynesians on islands several thousand miles apart. His theory was that they had originally come from Malaysia or Micronesia. French navigators were sure that they could not be related to the dark-skinned Melanesians in the vicinity of New Guinea.
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The classification of three general groups of Pacific islanders - Polynesians ("many islands"), Melanesians ("dark islands") and Micronesians ("little islands") - was itself a European invention.
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Until recently, several archaeologists and linguists supported a view that ancestors of the Polynesians left Taiwan and China 3,600 to 6,000 years ago. They spread through the Pacific relatively swiftly, largely bypassing Melanesia, which would explain why the Polynesians are not dark-skinned but speak an Austronesian language, rooted in Taiwan, instead of a Papuan language in parts of Melanesia. This view became known as the "express train" model.
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But the model soon ran into trouble. Nothing resembling prototypes of the Lapita pottery has been found in Taiwan or southern China. They first show up in the Melanesian Bismarcks. Although early genetic studies seemed to support the model, more recent ones reveal that the ancestors must have stopped off in Melanesia for considerable interbreeding, which has left clear genetic markers in today's Polynesians.
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Mark Stoneking, an anthropologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, said that the express-train model in its simplest form failed the genetic test and that the debate now focused on where the intermarriage took place and how extensive it was.
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Quoted in an article last year in the journal Science, Mr. Stoneking proposed that "the ancestors of Polynesians were Austronesians who moved out of Southeast Asia - not necessarily Taiwan - whose population expanded along the coast of New Guinea, intermingled and then moved out into Polynesia."
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Or as Patrick Kirch, director of the Hearst Museum of Anthropology at the University of California at Berkeley, said, the migration "was a train that dropped off boxcars along the way, encountering other human groups, interacting with them, exchanging cultures and sharing genes." NEW YORK The archaeologist David Burley looked out on Fanga 'Uta Lagoon and tried to think like ancient seafarers. Here, at the head of the lagoon, is where the first of their outrigger canoes must have pulled in, concluding heroic voyages of hundreds, perhaps more than a thousand miles from the west. So here he decided to dig on the South Pacific island of Tongatapu in the kingdom of Tonga.
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Although the site had been excavated before, Mr. Burley, of Simon Fraser University in British Columbia, made a new and revealing discovery concerning a fiercely debated issue in archaeology: the origin and migration routes of the Polynesians. What he found were shards of the distinctively decorated pottery of the Lapita peoples, cultural ancestors to modern Polynesians. Radiocarbon dating of charcoal among the shards showed that seafarers had reached the Tonga islands between 900 and 850 B.C., making this the earliest known settlement in Polynesia.
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Tongatapu, probably served as the initial staging point for population expansion to other islands of Tonga and into Samoa. The place seemed to be what anthropologists and geneticists call a founding colony. These people, he said, must have "formed the gene pool for all the rest of Polynesia."
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International Herald Tribune
3-D Models Give Proteins Shape
Researchers trying to discover drugs have more data than they can sift through, so many are using computer modeling to deal with the data. But not everyone trusts computer models enough to bet their businesses on them.
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www.wired.com
Permanent genetics exhibit opens in Chicago
Visitors to a new genetics exhibit can explore the mysteries of DNA, witness a virtual human embryo in action and gaze at cloned mice, mutant flies and hatching chicks.
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abcnews.go.com
Caltech Team Finds Cheaper Gene-Transplant Method
California scientists have found a better way to make glowing mice -- and rats, too.
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abcnews.go.com
Microbe breaks down PCBs
tiny microbe identified by University of Maryland researchers could be a powerful warrior against a persistent and dangerous pollutant.
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The Washington Times
Saskatoon organic farmers file lawsuit against Monsanto and Aventis
A group of organic farmers filed a class-action lawsuit on Thursday against seed giants Monsanto and Aventis for damage they allege was caused by genetically modified canola and to stop the introduction of genetically modified wheat.
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C-News
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