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Scientists Link a Prolific Gene Tree to the Manchu Conquerors of China
By NICHOLAS WADE, The New York Times, November 1, 2005
Geneticists have identified a major lineage of Y chromosomes in populations of northern China that they believe may mark the bearers as descendants of one of the Manchu conquerors who founded the Qing dynasty and ruled China from 1644 to 1911.
Because the founder of the lineage lived some 500 years ago, according to calculations based on the rate of genetic change, he may have been Giocangga, who died in 1582, the grandfather of the Manchu leader Nurhaci. At least 1.6 million men now carry this Manchu Y chromosome, says Chris Tyler-Smith, the leader of a team of English and Chinese geneticists.
Several historians, however, expressed reservations and said they would like to see more evidence, including testing of present-day descendants of the Qing nobility.
This is not the first instance of extraordinary male procreation that Dr. Tyler-Smith has brought to light. Two years ago, after a survey of Y chromosomes across East Asia, he identified a lineage that he was able to associate with the Mongol royal house and Genghis Khan.
Some 16 million men who live within the boundaries of the former Mongol empire now carry Genghis's Y chromosome, according to Dr. Tyler-Smith's calculations.
The Mongol Y chromosome presumably spread so widely because of the large number of concubines amassed by Genghis and his relatives. The Manchu rulers, though not in Genghis's league, also were able to spread their lineage so far, Dr. Tyler-Smith and his colleagues suggest, because of being able to keep many concubines. Even a ninth-rank nobleman in the dynasty (whose name is pronounced ching) was entitled to receive 11 kilograms of silver and 22,000 liters of rice as his annual stipend.
With colleagues in England and Beijing, Dr. Tyler-Smith identified a Y chromosome lineage that was surprisingly common among seven populations scattered across northern China, but was absent from the Han, to which most Chinese belong.
Since the only other Y chromosome lineage in the region anywhere near as common was that of Genghis Khan, the founder of the new lineage seemed likely to have left his mark in the historical record, as well, Dr. Tyler-Smith says in an article to appear in the December issue of The American Journal of Human Genetics. The Manchus of the Qing dynasty seem the best candidates because there were more than 80,000 official members of the Qing dynasty by 1911, according to a history of the Manchus by Prof. Mark C. Elliott of Harvard.
By counting the number of mutations in the lineage's Y chromosome, Dr. Tyler-Smith estimated that the common ancestor of all branches of the lineage lived about 500 years ago and was therefore probably the Manchu patriarch Giocangga.
A puzzling feature of the geneticists' finding is that the Manchu Y chromosome they identified is quite rare in Liaoning, the original home province. Dr. Elliott said that was not necessarily surprising, because many Manchus left their homeland and relocated to Beijing after the founding of the Qing dynasty. Also, the Communist government allowed many Han who worked for the Manchu in Liaoning to claim Manchu ethnicity.
Dr. James Lee, a historical demographer at the University of Michigan, said in an e-mail message from Beijing that the claim to have found a genetic link to the Qing imperial nobility in northern ethnic groups "seems quite forced," because most of the nobility lived in Beijing and Liaoning.
Dr. Tyler-Smith responded that his colleagues in Beijing had approached several documented descendants of the nobility and invited them to participate but none accepted.
After the Cultural Revolution, descent from the nobility was generally hidden, and many documents were destroyed, Dr. Tyler-Smith and colleagues write in their article. Because they could not find living Qing noblemen to test, they write, "Our hypothetical explanation remains unproven," despite "strong circumstantial support."
Dr, Elliott said that he knew several people who were well-attested descendants of the Qing royal family and that an ad in a Beijing newspaper should recruit a few hundred people, if not a few thousand.
Dr. Elliott said the Qing often contracted marriages with the Mongols as a means of securing political alliances, which would explain the presence of the Manchu chromosome in Mongolia. This could have also occurred with other northern ethnic groups where the Manchu chromosome is common, like the Oroqen, Hezhe and Ewenki, although those forest peoples "did not intermarry with the Qing imperial lineage, at least not in any appreciable numbers," he said.
The fathering of many children by a single man is an instance of what biologists call male intrasexual selection. Dr. Tyler-Smith said the Manchu and Mongol chromosomes were the only genetic imprints of this size that he can see in the populations of East Asia, but that there are likely to be other instances elsewhere.
Ginseng May Reduce Number and Severity of Colds
By NICHOLAS BAKALAR, The New York Times, November 1, 2005
Ginseng, long recommended as a treatment for colds by proponents of herbal medicine, has gained some support in a controlled scientific experiment. Canadian researchers tested North American ginseng extract against a placebo and found that it had a small but significant effect in reducing the number and intensity of colds.
The study, published in the Oct. 25 issue of The Canadian Journal of Medicine, tested 323 subjects. Volunteers were randomly assigned either to a group that took 200-milligram tablets of a commercial product with a known quantity of North American ginseng extract or to a group that took identical tablets of rice powder. An independent company randomly assigned the subjects, and neither the researchers nor the volunteers knew which pills were given to which participants.
The subjects were asked to note their symptoms - runny nose, fever, headache, sore throat and six others - and to rank them on a scale from 0 (no symptom) to 3 (severe symptom). The participants also kept logs of their symptoms, and the researchers called each volunteer once a month in the four-month study to make sure that they were taking their medicine.
At the end of two months, the subjects returned any unused medicine, and they were given a second bottle of pills. They then returned the unused amounts from those bottles at the end of the study, which was conducted in 2003-2004.
Of those in the placebo group, 23 percent reported two or more colds over the winter. Ten percent of the ginseng group had two or more. When those in the ginseng group did have colds, their symptoms were milder, based on the 0 to 3 rankings, and they had one-third fewer days with symptoms than those on the placebo.
The average duration of each cold was also lower in the ginseng group, 8.7 days compared with 11.1 days for the placebo group. On every measure, the people taking the ginseng did better than those on the placebo.
CV Technologies, the manufacturers of the ginseng-based cold treatment in the study, provided financial support for the study, but had no role in planning its design, collecting data or making decisions on preparing the manuscript for publication.
Dr. Tapan Basu, a professor of nutritional biochemistry at the University of Alberta and the lead author on the study, emphasized that the results pertained only to the standardized product in the study, and not to ginseng in general. "This is not the same as a bottle of ginseng from just anywhere," Dr. Basu said.
Dr. Ronald B. Turner, a professor of pediatrics at the University of Virginia who wrote an editorial accompanying the paper, warned that the study was only a first step. "This is an unexpected result," he said, "and the proper way to deal with it is to see what happens when other people try to confirm it.
"It's premature for the public to take off on this," he said.
The authors acknowledged that ginseng's effects in the study, while statistically significant, were still quite modest. They also pointed out that their experiment, carried out in flu season, was not set up to distinguish a cold from the flu.
Nevertheless, the authors said, the results with ginseng were slightly better than those reported with common antiviral drugs. North American ginseng extract, they concluded, "appears to be an attractive natural prophylactic treatment for upper respiratory tract infections."
Q & A: A Low Roar
By C. CLAIBORNE RAY, The New York Times, November 1, 2005
Q. I often wear earplugs to sleep or at loud concerts. Could I hurt my ears by wearing them so much?
A. Earplugs pushed too far into the ear can pack wax painfully deep into the ear canal, and they can cause irritations, abrasions and infections of the skin that they touch. But if you haven't experienced this after prolonged use, you probably have nothing to worry about and are very likely protecting your hearing.
Some authorities recommend earphone-style protection or specially fitted earplugs instead of commercial sponge or wax plugs, but in general the problem with earplugs is that too few people wear them.
The National Institute on Deafness and Other Communication Disorders of the National Institutes of Health regularly hands out earplugs in its campaigns against an epidemic of noise-induced hearing loss.
A recent study by Harvard researchers found that 61 percent of those who had attended concerts experienced hearing impairment or ringing in the ears, known as tinnitus, but that only 14 percent wore earplugs. The study, published in the journal Pediatrics, was based on responses to an MTV survey from 9,693 people.
Even short-term exposure to very loud noise can cause permanent damage, according to the Institute on Deafness.
It recommends using hearing protection whenever loud noises are unavoidable, at an airport job, for example, or predictably, at a rock concert.
Persistent Astronomers Find Pluto Has Two More Moons
By KENNETH CHANG, The New York Times, November 1, 2005
And then there were three.
Astronomers using NASA's Hubble Space Telescope announced yesterday that they had spotted two small moons circling Pluto. That gives Pluto, the smallest of the nine planets, a total of three moons, or more than four of the other planets.
"I can't really say we're really surprised," said Hal Weaver, a planetary scientist at Johns Hopkins University's Applied Physics Laboratory in Laurel, Md., a co-leader of the observations. "We proposed this, to look for satellites around Pluto."
Other astronomers had not been as optimistic. "Pretty much the community said: 'Eh, why are you looking? You're not going to find anything,' " said another Hubble team member, Marc W. Buie, at the Lowell Observatory in Flagstaff, Ariz.
The proposal was turned down twice before being approved in September 2004, Dr. Weaver said.
Pluto's largest moon, Charon, was discovered in 1978. Hubble spotted the second and third moons on May 15 and May 18. For now they are known only as S/2005 P1 and S/2005 P2. S/2005 P1, estimated to orbit 40,000 miles from Pluto, is up to 100 miles wide. P2 is likely 10 to 15 percent smaller and about 30,000 miles from Pluto.
The discovery does not directly play into the recent debate of whether Pluto should be considered a planet; a moon is not a prerequisite for planethood. (Mercury and Venus have none.) The discovery, however, will aid planning for NASA's New Horizons mission, which will be the first spacecraft to visit Pluto. It is scheduled for launching next year.
"We'll have to divide our attention four ways instead of two," said S. Alan Stern, director of the Southwest Research Institute's Department of Space Studies in Boulder, Colo., the principal investigator for New Horizons. He was also a co-leader of the discovery team.
Astronomers believe that Charon formed in the aftermath of a collision between a large meteor and Pluto. Dr. Stern said that he thought the new moons also formed out of that collision and that there could be more. "There should be more shards of that impact," he said.
Another possibility is that the two moons were originally part of the Kuiper Belt, the ring of small icy bodies beyond Neptune, and were captured by Pluto's gravitational pull.
Dr. Stern said the new moons also raised the possibility that Pluto could have a ring like the much larger Saturn, formed from debris shed by the moons. Because Charon is much larger with stronger gravity, debris kicked up from its surface is pulled back down.
By NICHOLAS WADE, The New York Times, November 1, 2005
Geneticists have identified a major lineage of Y chromosomes in populations of northern China that they believe may mark the bearers as descendants of one of the Manchu conquerors who founded the Qing dynasty and ruled China from 1644 to 1911.
Because the founder of the lineage lived some 500 years ago, according to calculations based on the rate of genetic change, he may have been Giocangga, who died in 1582, the grandfather of the Manchu leader Nurhaci. At least 1.6 million men now carry this Manchu Y chromosome, says Chris Tyler-Smith, the leader of a team of English and Chinese geneticists.
Several historians, however, expressed reservations and said they would like to see more evidence, including testing of present-day descendants of the Qing nobility.
This is not the first instance of extraordinary male procreation that Dr. Tyler-Smith has brought to light. Two years ago, after a survey of Y chromosomes across East Asia, he identified a lineage that he was able to associate with the Mongol royal house and Genghis Khan.
Some 16 million men who live within the boundaries of the former Mongol empire now carry Genghis's Y chromosome, according to Dr. Tyler-Smith's calculations.
The Mongol Y chromosome presumably spread so widely because of the large number of concubines amassed by Genghis and his relatives. The Manchu rulers, though not in Genghis's league, also were able to spread their lineage so far, Dr. Tyler-Smith and his colleagues suggest, because of being able to keep many concubines. Even a ninth-rank nobleman in the dynasty (whose name is pronounced ching) was entitled to receive 11 kilograms of silver and 22,000 liters of rice as his annual stipend.
With colleagues in England and Beijing, Dr. Tyler-Smith identified a Y chromosome lineage that was surprisingly common among seven populations scattered across northern China, but was absent from the Han, to which most Chinese belong.
Since the only other Y chromosome lineage in the region anywhere near as common was that of Genghis Khan, the founder of the new lineage seemed likely to have left his mark in the historical record, as well, Dr. Tyler-Smith says in an article to appear in the December issue of The American Journal of Human Genetics. The Manchus of the Qing dynasty seem the best candidates because there were more than 80,000 official members of the Qing dynasty by 1911, according to a history of the Manchus by Prof. Mark C. Elliott of Harvard.
By counting the number of mutations in the lineage's Y chromosome, Dr. Tyler-Smith estimated that the common ancestor of all branches of the lineage lived about 500 years ago and was therefore probably the Manchu patriarch Giocangga.
A puzzling feature of the geneticists' finding is that the Manchu Y chromosome they identified is quite rare in Liaoning, the original home province. Dr. Elliott said that was not necessarily surprising, because many Manchus left their homeland and relocated to Beijing after the founding of the Qing dynasty. Also, the Communist government allowed many Han who worked for the Manchu in Liaoning to claim Manchu ethnicity.
Dr. James Lee, a historical demographer at the University of Michigan, said in an e-mail message from Beijing that the claim to have found a genetic link to the Qing imperial nobility in northern ethnic groups "seems quite forced," because most of the nobility lived in Beijing and Liaoning.
Dr. Tyler-Smith responded that his colleagues in Beijing had approached several documented descendants of the nobility and invited them to participate but none accepted.
After the Cultural Revolution, descent from the nobility was generally hidden, and many documents were destroyed, Dr. Tyler-Smith and colleagues write in their article. Because they could not find living Qing noblemen to test, they write, "Our hypothetical explanation remains unproven," despite "strong circumstantial support."
Dr, Elliott said that he knew several people who were well-attested descendants of the Qing royal family and that an ad in a Beijing newspaper should recruit a few hundred people, if not a few thousand.
Dr. Elliott said the Qing often contracted marriages with the Mongols as a means of securing political alliances, which would explain the presence of the Manchu chromosome in Mongolia. This could have also occurred with other northern ethnic groups where the Manchu chromosome is common, like the Oroqen, Hezhe and Ewenki, although those forest peoples "did not intermarry with the Qing imperial lineage, at least not in any appreciable numbers," he said.
The fathering of many children by a single man is an instance of what biologists call male intrasexual selection. Dr. Tyler-Smith said the Manchu and Mongol chromosomes were the only genetic imprints of this size that he can see in the populations of East Asia, but that there are likely to be other instances elsewhere.
Ginseng May Reduce Number and Severity of Colds
By NICHOLAS BAKALAR, The New York Times, November 1, 2005
Ginseng, long recommended as a treatment for colds by proponents of herbal medicine, has gained some support in a controlled scientific experiment. Canadian researchers tested North American ginseng extract against a placebo and found that it had a small but significant effect in reducing the number and intensity of colds.
The study, published in the Oct. 25 issue of The Canadian Journal of Medicine, tested 323 subjects. Volunteers were randomly assigned either to a group that took 200-milligram tablets of a commercial product with a known quantity of North American ginseng extract or to a group that took identical tablets of rice powder. An independent company randomly assigned the subjects, and neither the researchers nor the volunteers knew which pills were given to which participants.
The subjects were asked to note their symptoms - runny nose, fever, headache, sore throat and six others - and to rank them on a scale from 0 (no symptom) to 3 (severe symptom). The participants also kept logs of their symptoms, and the researchers called each volunteer once a month in the four-month study to make sure that they were taking their medicine.
At the end of two months, the subjects returned any unused medicine, and they were given a second bottle of pills. They then returned the unused amounts from those bottles at the end of the study, which was conducted in 2003-2004.
Of those in the placebo group, 23 percent reported two or more colds over the winter. Ten percent of the ginseng group had two or more. When those in the ginseng group did have colds, their symptoms were milder, based on the 0 to 3 rankings, and they had one-third fewer days with symptoms than those on the placebo.
The average duration of each cold was also lower in the ginseng group, 8.7 days compared with 11.1 days for the placebo group. On every measure, the people taking the ginseng did better than those on the placebo.
CV Technologies, the manufacturers of the ginseng-based cold treatment in the study, provided financial support for the study, but had no role in planning its design, collecting data or making decisions on preparing the manuscript for publication.
Dr. Tapan Basu, a professor of nutritional biochemistry at the University of Alberta and the lead author on the study, emphasized that the results pertained only to the standardized product in the study, and not to ginseng in general. "This is not the same as a bottle of ginseng from just anywhere," Dr. Basu said.
Dr. Ronald B. Turner, a professor of pediatrics at the University of Virginia who wrote an editorial accompanying the paper, warned that the study was only a first step. "This is an unexpected result," he said, "and the proper way to deal with it is to see what happens when other people try to confirm it.
"It's premature for the public to take off on this," he said.
The authors acknowledged that ginseng's effects in the study, while statistically significant, were still quite modest. They also pointed out that their experiment, carried out in flu season, was not set up to distinguish a cold from the flu.
Nevertheless, the authors said, the results with ginseng were slightly better than those reported with common antiviral drugs. North American ginseng extract, they concluded, "appears to be an attractive natural prophylactic treatment for upper respiratory tract infections."
Q & A: A Low Roar
By C. CLAIBORNE RAY, The New York Times, November 1, 2005
Q. I often wear earplugs to sleep or at loud concerts. Could I hurt my ears by wearing them so much?
A. Earplugs pushed too far into the ear can pack wax painfully deep into the ear canal, and they can cause irritations, abrasions and infections of the skin that they touch. But if you haven't experienced this after prolonged use, you probably have nothing to worry about and are very likely protecting your hearing.
Some authorities recommend earphone-style protection or specially fitted earplugs instead of commercial sponge or wax plugs, but in general the problem with earplugs is that too few people wear them.
The National Institute on Deafness and Other Communication Disorders of the National Institutes of Health regularly hands out earplugs in its campaigns against an epidemic of noise-induced hearing loss.
A recent study by Harvard researchers found that 61 percent of those who had attended concerts experienced hearing impairment or ringing in the ears, known as tinnitus, but that only 14 percent wore earplugs. The study, published in the journal Pediatrics, was based on responses to an MTV survey from 9,693 people.
Even short-term exposure to very loud noise can cause permanent damage, according to the Institute on Deafness.
It recommends using hearing protection whenever loud noises are unavoidable, at an airport job, for example, or predictably, at a rock concert.
Persistent Astronomers Find Pluto Has Two More Moons
By KENNETH CHANG, The New York Times, November 1, 2005
And then there were three.
Astronomers using NASA's Hubble Space Telescope announced yesterday that they had spotted two small moons circling Pluto. That gives Pluto, the smallest of the nine planets, a total of three moons, or more than four of the other planets.
"I can't really say we're really surprised," said Hal Weaver, a planetary scientist at Johns Hopkins University's Applied Physics Laboratory in Laurel, Md., a co-leader of the observations. "We proposed this, to look for satellites around Pluto."
Other astronomers had not been as optimistic. "Pretty much the community said: 'Eh, why are you looking? You're not going to find anything,' " said another Hubble team member, Marc W. Buie, at the Lowell Observatory in Flagstaff, Ariz.
The proposal was turned down twice before being approved in September 2004, Dr. Weaver said.
Pluto's largest moon, Charon, was discovered in 1978. Hubble spotted the second and third moons on May 15 and May 18. For now they are known only as S/2005 P1 and S/2005 P2. S/2005 P1, estimated to orbit 40,000 miles from Pluto, is up to 100 miles wide. P2 is likely 10 to 15 percent smaller and about 30,000 miles from Pluto.
The discovery does not directly play into the recent debate of whether Pluto should be considered a planet; a moon is not a prerequisite for planethood. (Mercury and Venus have none.) The discovery, however, will aid planning for NASA's New Horizons mission, which will be the first spacecraft to visit Pluto. It is scheduled for launching next year.
"We'll have to divide our attention four ways instead of two," said S. Alan Stern, director of the Southwest Research Institute's Department of Space Studies in Boulder, Colo., the principal investigator for New Horizons. He was also a co-leader of the discovery team.
Astronomers believe that Charon formed in the aftermath of a collision between a large meteor and Pluto. Dr. Stern said that he thought the new moons also formed out of that collision and that there could be more. "There should be more shards of that impact," he said.
Another possibility is that the two moons were originally part of the Kuiper Belt, the ring of small icy bodies beyond Neptune, and were captured by Pluto's gravitational pull.
Dr. Stern said the new moons also raised the possibility that Pluto could have a ring like the much larger Saturn, formed from debris shed by the moons. Because Charon is much larger with stronger gravity, debris kicked up from its surface is pulled back down.
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