Health hazards of High Tech Rooms

The amount of work-related illness is likely to soar over the next 10 years, research has found. The study, commissioned by Norwich Union Healthcare, found that far from improving the working environment, the march of new technology could lead to an epidemic of sickness-related industrial claims.

Nearly three-quarters of GPs surveyed predicted that the number of patients suffering from work-related illness will rise over the coming decade.

Personnel directors took an equally gloomy view. Nearly half admitted that technological advances in the workplace were creating new complaints, while 68% said companies needed to re-think their approach to occupational health.

Among the complaints which are set to become commonplace are repetitive strain injury (RSI), bad backs and eye strain.

Challenges for the millennium

Sue Summers, Norwich Union Healthcare spokesperson, said: "Managers will face all sorts of challenges in the new millennium, not least the possibility of increased staff absence resulting from today’s office environment.

"Our research shows that companies need to start thinking about re-evaluating the way in which they look after the health of their employees - in order to ensure their workplace is a safe and healthy environment."

The research was welcomed by the Heath and Safety Executive, which said positive action was needed to raise awareness of "modern occupational health challenges".

The survey was based on responses from 100 GPs and 100 personnel directors.

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How Cellphone -Tower Radiation Affects Us?

With mobile phones now as ubiquitous as their land-line counterparts, few people worry about the potential health risks associated with flipping open a handset or standing near a cell tower.

But among researchers who study the effects of electromagnetic emissions from mobile phones and towers, the prevailing wisdom is that it’s too early to conclude that they are harmless to humans.

"At the moment, there are too few properly controlled scientific studies to draw any strong conclusions," said Elaine Fox, a professor in the psychology department at the University of Essex who is studying whether the electromagnetic fields emitted from mobile-phone base stations have a direct effect on human health.

Fox’s project is one of several that received funding last month from the United Kingdom’s Mobile Telecommunications and Health Research program, a group formed in 2001 to report on whether exposure to cell-phone radiation adversely affects people’s health. The group formed following the publication of a report that failed to find evidence of health risks, but noted that research to date was not expansive enough to conclude that no dangers exist.

Topics of past research include the potential link between brain tumors and mobile-phone use, effects of mobile-phone radiation on blood pressure, and the possible link between cancer incidence in early childhood and proximity to mobile-phone base stations.

As part of the current studies, researchers are examining the scientific basis of "electrical sensitivity," a collection of symptoms, such as headaches and fatigue, that some people believe is caused by exposure to wireless phones and towers.

Fox’s research, an extension of a volunteer study that begun in January, will investigate whether some people are particularly sensitive to cell-phone electromagnetic fields. In the first stage of the project, Fox collected survey results from 4,000 participants, about 6 percent of whom indicated some degree of symptoms, such as headaches or burning skin, that they attributed to electromagnetic fields.

The second part of the project, launched in November, involves testing people who identify themselves as hypersensitive to electromagnetic fields alongside people who are not, to establish whether mobile-phone base stations really are affecting health and well-being.

Another research group, based at King’s College in London, is testing 120 people, half of whom consider themselves hypersensitive to mobile-phone emissions. James Rubin, a research fellow at King’s College who is overseeing the project, is hoping to submit findings for publication by the end of next year, provided he finds enough volunteers.

"People who report being hypersensitive to mobiles are often understandably cautious about taking part in a study which involves exposure to a mobile-phone signal," he said. The study will examine whether mobile-phone signals cause such symptoms as headaches, nausea, dizziness and fatigue, and whether they affect the levels of certain hormones that are important in regulating metabolism.

Since cell-phone adoption reached critical mass in the mid-1990s, research into the effects of long-term mobile-phone usage has also become more feasible. However, representatives of the cell-phone industry say they have yet to see any findings that should give mobile users reason for alarm.

"There is no conclusive evidence that wireless phones contribute to health risks, and the same goes for towers," said Erin McGee, a spokeswoman for the Cellular Telecommunications Industry Association.

The U.S. Food and Drug Administration takes a similar position on health risks caused by mobile-phone base stations.

"Measurements made near cellular and PCS base-station antennas mounted on towers have confirmed that ground-level exposures are typically thousands of times less than the exposure limits adopted by the (Federal Communications Commission)," the agency states on its website.

The FDA also maintains that there’s no scientific evidence to link any health problems to mobile-phone use. On the other hand, the agency says there is no proof that they are absolutely safe.

The World Health Organization, meanwhile, expects to complete health-risk assessments in 2007 under its International EMF Project, which examines effects of exposure to electric and magnetic fields up to 300 GHz in frequency, which includes cellular-phone emissions.

Libby Kelly, executive director of the Council on Wireless Technology Impacts, an activist group favoring greater regulation of electromagnetic emissions, believes health agencies are understating the risks posed by wireless phones and towers.

She cited a study released in October by Sweden’s Karolinska Institute, which found that 10 or more years of mobile-phone use increases the risk of acoustic neuroma -- a benign tumor on the auditory nerve. However, the study was conducted on analog mobile phones that had been in use for more than a decade, and researchers said they could not say whether results would be similar after long-term use of digital phones.
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Wi-Fi Causes Health Problem : Report

Electromagnetic field sensitivity is an empirical chimera.

Riding in on peer-reviewed research, but flunking every major test, the idea that wireless technology amounts to a modern health threat presents a conundrum to proponents and skeptics alike. With Wi-Fi networks blanketing homes, schools and even whole cities, they’ve become the latest flash point in a struggle that’s arced from power lines to microwaves, cell phones and even computers, spanning decades of debate.

To sufferers of EMF sensitivity, however, such academic battles are exasperating. To them, it’s as if their symptoms, and even their sanity, are under attack. "A professor called it Compulsive Risk Assessment Psychosis, otherwise known as CRAP,’" said Rod Read of ElectroSensitivity-UK, a registered charity in Britain. "He says everyone is deluded. It insults and abuses people who are sick. I thought that went out with the Victorian era."

British author Kate Figes recently described a sensation akin to being "prodded all over your body by 1,000 fingers" when in the presence of a Wi-Fi signal. When Michael Bevington fell ill, he blamed a network recently installed at the prestigious school where he’d worked for 28 years: "Over the weekend, away from the classroom, I felt completely normal."

Plans for a Wi-Fi network at an Illinois school were scuppered after parents filed a lawsuit. The president of Canada’s Lakehead University banned Wi-Fi on campus, likening it to second-hand smoke. In March, Toronto’s public health department questioned plans to install a citywide network. ’It’s the whole insidious and invisible exploitation of the EM spectrum," said Read, who estimates between 1 percent and 3 percent of the population may be susceptible. "To the sensitive, it’s like being shouted at all the time."

Sufferers report headaches, nausea, stomach upsets, tinnitus, brain fog and short-term memory among the symptoms, Read said. Skeptics, however, suspect that blaming EMF sensitivity for their ills amounts to an easy answer to almost any medical problem. "There is no known mechanism by which EMF from any source -- power lines, cell phones or Wi-Fi networks -- can cause health problems of any kind," said Michael Shermer, publisher of Skeptic magazine. "In fact, there is nothing that even needs explaining."

While some groups focus on nonspecific symptoms, others claim links to more severe conditions such as cancer.

"We’re in it for a long fight," said Cindy Sage of Sage EMF Design, a California environmental consulting firm that profiles locations for their EMF characteristics. "Around the world, we’ve seen the affected giving up hope. But they’re burning down cell towers in Israel, dismantling them in Ireland, taking it to a civil disobedience level when they can’t get their governments to respond."

Scientists recognize the dangers of high-frequency ionizing radiation, such as gamma rays unleashed by nuclear fallout. Non-ionizing radiation, however, such as Wi-Fi signals, cellular networks, television broadcasts and visible light, cannot break down atomic bonds and has long been considered safe.

"The fields that are induced by Wi-Fi transmissions are well below those that could cause problems to humans," said Chris Guy, head of The University of Reading’s School of Systems Engineering. "The maximum power that is allowed to be transmitted by any Wi-Fi unit is one-tenth of a watt."

EMF sensitivity advocates, however, believe studies reveal that even these low-frequency, low-power fields can cause subtle damage to human tissue, citing evidence of cell death, faster-growing tumors and DNA damage.

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Are Computers Slowly Killing You?

The first thing to know is that the risks are not likely to affect you unless you are a "habitual" computer user. In other words, you’re sitting at the computer pretty much all day, every day. Oh yeah... that’s all of us! That’s not to say that the occasional computer user won’t have problems. Everyone’s level of sensitivity is unique.

The buzz started in the 80’s and culminated in the 1992 Health and Safety DSE (Display Screen Equipment) regulations. Then came Carpal-Tunnel Syndrome followed by ergonomics. The hype has subsided, since we all know the computer isn’t going to kill us - but we have learned a lot over the past 20 years about potential health risks and more importantly, we’ve learned ways to avoid being at risk when we’re using computers. Let’s look at some of the most common medical problems and what you can do to avoid them.

Eye Strain:

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  Position your terminal at right angles to the window if possible; avoid facing directly into bright light (coming at you from behind your computer screen).


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  Install an anti-glare screen.


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  Adjust the brightness controls on the screen until they are comfortable to your eyes.

Carpal Tunnel Syndrome:

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  Adjust your chair or table height to have your elbow angle at 90-100 degrees.
  Position your keyboard so that you don’t have to bend your hands uncomfortably upward to reach the keys; place a raised wrist rest on the table in front of the keyboard if necessary.
  
  
• 
  
  Clinch your fists, hold for one second, then stretch your fingers out wide and hold for 5 seconds.
  
  
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  Organize your workday, if possible, to intersperse other tasks with your computer work so that you’re not sitting at the computer for several hours without a break. Variety is key.
  
  
• 
  
  Hold the mouse loosely and click lightly.

Neck and Back Strain:

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  Check your posture - sit up straight.
  
  
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  The monitor screen surface should be approximately 18-24 inches away from your torso.
  
  
• 
  
  Preferably chairs should be on wheels, have backrest tilt adjustment, and have arms.
  
  
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  Be sure you have enough desktop space for work papers and other equipment.

Conjunctivitis (itchy, bloodshot eyes) and Dermatitis:

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  Be sure the screen doesn’t flicker or wave - this could indicate that service or adjustment is needed.
  
  
• 
  
  Look away from the screen periodically.
  
  
• 
  
  Don’t forget to blink - your eyes need the moisture.

The next wave of health concerns focuses on electromagnetic fields and the cathode ray tube in the computer screen showering us with negatively charged electrons. But don’t let that keep you up at night. It’s best to follow the preventive steps listed above, which by the way are things YOU can do without spending a penny.

This summary was gathered from a variety of sources and is provided as a primer to inspire you to research further on your own. If you’d like to explore the subject further, try these resources:

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Cars warns about hazards

A huge European project dealing with car and road safety has developed a system that will read satellite navigation maps and warn the driver of upcoming hazards, sharp bends, dips and accident black spots, which may be invisible to the driver.

Even better, the system can update the geographic database, thus letting drivers themselves update the maps. Consider: You are driving along an unfamiliar road, using your satellite navigation to find your way. At the same time, smart technology in your car is tracking the route, recognising the terrain and upcoming bends and intersections, to keep you informed.

The PReVENT system is equipped with information on accident blind spots, dips in the road, and more. It can even link into other in-car wireless communication systems to communicate with other vehicles in the vicinity.

"The analysis of many situations can be dramatically improved by an awareness of the location," says Matthias Schulze, coordinator of the EU-funded project. PReVENT, comprising of more than a dozen projects, focuses on specific road safety issues, with all individual projects supporting and feeding each other in some way. It means the impact is greater than the sum of its parts.

For example, one project known as MAPS&ADAS works on the development, testing and validation of safety-enhanced digital maps. The project is also involved with creating a standard interface for an ADAS (Advanced Driver Assistance System).

Other components such as ’LateralSafe’ use sensors to scan the blind-spot lane and your current lane, while ’SafeLane’ ensures that drivers stay in the correct lane. InterSafe, another sub-project, would help negotiate intersections: A new traffic light, installed with a wireless alert system developed by InterSafe, can warn oncoming cars of its existence and that it is about to turn red.

MAPS&ADAS developed a protocol whereby the car can compare that information to the data supplied on the map. If the new traffic light is not marked on the map, the car can update the map database. "A lot of the sub-projects took advantage of each other’s work," Schulze says.

"Ultimately, it would mean that cars are updating existing maps all the time. It is an elegant application with enhanced functionality that shows how existing technology can squeeze the maximum out of the installed base," he adds. But it could be a long time before that sort of map-making functionality becomes available. It requires transmitters installed in the streetscapes across the landscape, warning cars of upcoming hazards.

"We did not fully develop this technology, but we developed the protocols and systems required to set it up, so that when the infrastructure is in place, it can be quickly integrated into new systems," Schulze informs. It all means that ’map reading for dummies’ technology could be transformed into a very, very smart safety system.

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Remote lie detection raises ethical issues

A new way to remotely monitor blood pressure, pulse rate and sweating could be used to screen for health signs as well as to administer lie detection tests on people without their knowledge or consent.

While researchers stress their work remains only proof-of-concept, a commercial version using sub-terahertz waves could theoretically help remotely monitor medical patients, evaluate athletic performance, diagnose disease and detect lies.

The key is in the surprising shape of human sweat ducts.Recent advances in imaging technology reveals that sweat ducts, the tiny tubes that connect sweat glands to the outside of the skin, are helical, or shaped like corkscrews.

"At this point it’s not clear why nature chooses to create sweat ducts shaped like antennas," says physicist Professor Aharon Agranat of the Hebrew University of Jerusalem and a co-author of a study in Physical Review Letters.

When co-author and colleague Professor Yuri Feldman saw these sweat gland images, they reminded him of the helical antennas often used in basic engineering classes.

First, look at the twists

By measuring certain factors like the number of twists, any beginning electrical engineering student can calculate the wavelength of energy the antenna would interact with, say the physicists.

The wavelength of human sweat glands falls in the sub-terahertz, or sub T-ray, range.Full T-rays have been used in a variety of other applications recently, from uncovering hidden artwork to finding concealed weapons. T-rays, unlike their energetic cousins x-rays, are harmless.

Next, build a machine

By creating a machine that generates and detects sub T-rays, the scientists say they can look at which wavelengths interact with the millions of tiny ’antennas’ buried within the body’s largest organ, the skin.

While sweating doesn’t produce T-rays, sweat production changes the wavelength that is bounced back off the sweat duct antenna.

By measuring these wavelengths, scientists can, in turn, calculate how much and where a person is sweating.

Then, look at the sweat

Different parts of the body sweat depending on the reason. Eating a spicy chilli pepper causes sweat beads to break out on the forehead. Sunbathing causes sweat glands to be activated on the chest and back.

Various diseases and medical conditions activate other sweat glands, while also changing blood pressure and pulse rate.Eventually, with the development of an accurate sweat map and other studies, the physicists hope to create a tool that can diagnose diseases based on where a person is sweating.

In later tests the researchers also measured blood pressure and pulse rate remotely, by monitoring the kinds of sweating directly linked to changes in these vital signs.

Remote monitoring

Currently the only way to measure blood pressure is by using an inflatable pressure cuff or a surgically implanted monitor. The only way to measure sweat is through a cumbersome process that uses electrodes on a small portion of skin.

The new method can do both remotely and constantly.While cautious about the new research, James Wolff, a doctor at Emerson Hospital in Concord, Massachusetts, who was not associated with the study, says "this could open up a whole new area of research".

Because it has never been possible to monitor sweat, pulse and blood pressure remotely, no one has thought about what the technique could be used for, says Wolff.

Sweaty liars

The device could also be used as a remote lie detector, without their knowledge or consent.When a person lies, it triggers physiological responses: faster pulse, higher blood pressure and increased sweating. A polygraph machine measures these responses, but it has to be physically attached to a person.

Trained professionals can evade polygraphs, but if a person doesn’t know they are being constantly tested the new method could be more effective.Jonathan Marks, a professor of bioethics at Pennsylvania State University, says that lie detection using this method would still have problems with accuracy.

A person already anxious over something else when they are being scanned could trigger a false positive."There are concerns about people’s privacy," says Marks. "Is there a justification for screening people en masse for physiological data?

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Electricity from stoves? Soon

If everything falls in place for him and his fellow researcher, Professor Arun Majumdar says a villager in India may be able to produce electricity for his home from a chullah, or a stove that uses wood, coal, dry leaves, or cow-dung to make fire.

During winter, instead of turning on heaters, a person anywhere in the world would be able to use a simple power-jacket utilising his body heat to stay warm. The same body heat could even be used to recharge a cell phone.If this sounds farfetched, you need to find out from Majumdar why he believes that day is not too far.

For years, Majumdar and fellow investigator Peidong Yang have been trying to see if energy routinely lost as heat during production of electricity could be harnessed using silicon nanowires.

About a year ago, Majumdar and his colleagues discovered it is possible to achieve substantial improvement in thermoelectric energy efficiency at room temperature in silicon nanowires. The high performance thermoelectric capability in silicon, Majumdar says, opens up tremendous possibilities for human welfare and cost savings.

"To give you an example," Majumdar said, "90 per cent of the world’s power is generated by heat, whether it is steam turbines, coal-fired power plants, or gas turbines. It is all heat-to-power conversion. These engines operate at approximately 30 to 40 per cent efficiency which means that about 60 to 70 per cent of the heat is lost.

"If we could convert even 2-3 per cent of that lost heat into electricity," he continued, "the number would be absolutely staggering. It is almost half the United States’ electrical capacity."

He said thermoelectric materials that have the ability to convert heat into electricity could be used to capture much of the heat that is currently wasted.

"These devices can be used both as power generators and also as refrigerators or air-conditioning devices. So the same devices, if you hook them up to a battery, will become a refrigerator. Thus if your jacket is filled with these devices on a
hot and humid day, you can carry your own air-conditioning in your jacket," Kolkata-born Majumdar, who came to the US in 1985 after a BTech in Mechanical Engineering from the Indian Institute of Technology- Bombay, said.

Majumdar, who holds nine patents and has authored a book and over 150 articles in journals, said the Berkeley Laboratory is not the only one doing such research.

"There are others like MIT [Massachusetts Institute of Technology] who are also into this. We are a community," he said.

He said a whole series of work started in 2001 and then he and his team observed something that pushed them to do further research and confirmed their findings over and over again until the discovery some months ago.

The results of the discovery were published in an article written by Majumdar and chemist Yang in the scientific magazine Nature in January.There is a challenge though in the otherwise bright prospect for the use of the new technology -- how to make it cost efficient and performance efficient. "It is actually a combination of performance and cost. The cost has to come down in order of magnitude. Right now if you buy one of these units -- which is about an inch by an inch -- it is about $10. This has to come down to $1 or less than a dollar, and the performance has to double. So, it is not easy," Majumdar said.

But the professor, whose research interests are in the broad area of energy conversion and storage in solid-state materials and devices, heat and charge transport in nanostructured materials, and electrochemical and bimolecular phenomena in micro- and nano-fluidic devices, is pretty hopeful about the future.

Asked what gives him confidence, Majumdar said the fact that one can do it in silicon gives rise to optimism. "Silicon has $10-billion industrial infrastructure, which is producing chips or electronics. If you can take that infrastructure and turn part of it towards energy, you do not have to do much.

"Silicon wafers are already cheap. The packaging and processing conditions are all known. The fact that this is happening in silicon is a big deal. That is a big promise," he said.

Majumdar, who got interested in nanotechnology about 20 years ago and for whom the ’profession has become a passion,’ says that the thermoelectric capabilities of silicon open up new vistas for making life easier and comfortable, especially in developing countries like India.

He says technology can enable people in rural areas to use local resources to generate electricity, citing the fact that there are many in India who are off the electricity grid.

"If you take a chullah for cooking and wrap a thermoelectric device around it, you would generate electricity. Similarly, if you take a kerosene lantern, which although is a very inefficient way of generating light, and wrap a thermoelectric
device on the top from where the heat goes up and use that waste heat, you can generate electricity for your home," Majumdar said.

"That is very much possible, if the cost costs come down and it becomes scalable," he said.

Majumdar does not want to specify how long one has to wait before the technology can be commercialized although he says there is somewhat of a pressure on them to start a company.

"But we are backing off a little at this stage because we want to do a little more research. From the promise of a material to reality of systems takes at least about 10 years," he said.

"When I said reality of systems, I mean that someone has to manufacture it, someone has to sell it and people have to use it. From that perspective a lot of work is still to be done," Majumdar said.

The research at the Berkeley Lab, which is a Department of Energy national laboratory, has been funded by the DEO’s Office of Basic Energy Science.

Majumdar is a member of the Nanotechnology Technical Advisory Group to the President’s Council of Advisors on Science and Technology. He served as the founding chair of the ASME Nanotechnology Institute, a former member of the Council of Materials Science & Engineering of the Department of Energy, and is currently Chair, Advisory Committee of the Engineering Directorate of the National Science Foundation.

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India to launch remote sensing satellite this month

India will later this month (April 2008) launch a remote sensing satellite equipped with high-resolution cameras and advanced scientific instruments, space agency officials said here.

Cartosat-2A, as the all-weather, reconnaissance satellite is called, will be used to plan urban and rural development projects. It can also be used for intelligence gathering, the officials said Friday.

"The tentative launch date is April 28," Indian Space Research Organisation chairman G. Madhavan Nair told reporters in Bangalore where the agency is based.

"The exact date and time will be finalised in a fortnight after factoring weather and other relevant data," he added.

Identical to the mapping satellite Cartosat-2, which was launched in January 2007, the 680-kilogram (1,500-pound) Cartosat-2A will be placed in a polar orbit at an altitude of 630 kilometres (391 miles).

The satellite will be launched by the Indian-developed rocket, the Polar Satellite Launch Vehicle, from the Sriharikota space station in southern India.

India started its space programme in 1963, and has since developed and put several of its own satellites into space. It has also designed and built launch rockets to reduce its dependence on overseas space agencies.

Space agency chairman Nair said the body has finalised a project report concerning a manned mission by 2014-15.

"The report is being submitted to the government for approval and budgetary allocation," he said. "The Space Commission, headed by Prime Minister Manmohan Singh, will meet next week or so to review the report and take a decision."

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Is DNA Repair A Substitute For Sex?

Birds and bees may do it, but the microscopic animals called bdelloid rotifers seem to get along just fine without sex, thank you. What’s more, they have done so over millions of years of evolution, resulting in at least 370 species. These hardy creatures somehow escape the usual drawback of asexuality - extinction - and the MBL’s David Mark Welch, Matthew Meselson, and their colleagues are finding out how.

In two related papers published recently in Proceedings of the National Academy of Sciences (PNAS), the team proposes an interesting hypothesis: Bdelloid rotifers have been able to give up sex and survive because they have evolved an extraordinary efficient mechanism for repairing harmful mutations to their DNA.

“We think, in the bdelloid rotifer, genomic changes together with environmental changes have conspired to create something that is able to exist in the absence of sex,” says Mark Welch, an assistant scientist in the MBL’s Josephine Bay Paul Center.

Their results have medical implications, because DNA repair capacity is an important factor in cancer, inflammation, aging, and other human conditions.

In animals that do have sex, DNA repair is accomplished during meiosis, when chromosomes pair up (one from the father, one from the mother) and “fit” genes on one chromosome can serve as templates to repair damaged genes on the other chromosome. The bdelloid, though, always seems to reproduce asexually, by making a clone of itself. How then, does it cope with deleterious mutations?

In the first PNAS paper, MBL adjunct scientist Matthew Meselson and Eugene Gladyshev, both of Harvard University, demonstrate the enormous DNA repair capacity of bdelloid rotifers by zapping them with ionizing radiation (gamma rays), which has the effect of shattering its DNA into many pieces. “We kept exposing them to more and more radiation, and they didn’t die and they didn’t die and they didn’t die,” says Mark Welch. Even at five times the levels of radiation that all other animals are known to endure, the bdelloids were able to continue reproducing.

“Because there is no source of such intense ionizing radiation on Earth, except if we make it, there is no way these organisms could have evolved to be radiation resistant,” says Mark Welch. Instead, they propose that bdelloids’ DNA repair capacity evolved due to a different environmental adaptation - tolerance of extreme dryness.

Bdelloids, which live in ephemeral aquatic habitats such as temporary freshwater pools and on mosses, are able to survive complete desiccation (drying out) at any stage of their life cycle. They just curl up and go dormant for weeks, months, or years, and when water becomes available, they spring back to life. Mark Welch and his colleagues showed that desiccation, like ionizing radiation, breaks up the rotifers’ DNA into many pieces. Presumably, the same mechanisms they use to survive desiccation as part of their life cycle also protect them from ionizing radiation.

“That’s the next thing we are looking at. How are the bdelloids able to repair this many double-stranded breaks in their DNA? Do they have better enzymes, more enzymes?” Mark Welch says.

One feature that may confer exceptional DNA repair capacity on the bdelloids is described in the team’s second PNAS paper. Here, they give evidence that the bdelloid rotifer, like most animals, originally had two copies of each chromosome. But at some point in its evolution, it underwent a “whole-genome duplication,” giving it four copies of each chromosome and hence of each gene. Normally, lineages that undergo whole-genome duplication lose the duplicate genes over time. The bdelloid, though, has kept most of its duplicate genes throughout its evolutionary history.

“We believe they have kept most of their duplicate genes because they are serving as templates for DNA repair,” says Mark Welch. One possible result of DNA repair is gene conversion, in which the gene being repaired ends up having an identical DNA sequence to the gene repairing it. This can introduce the kinds of changes into the gene pool that sex usually does. (For example, a gene coding for brown eyes may repair a gene coding for blue eyes on its paired chromosome, and end up turning the blue-eye gene into a brown-eye one.)

“We think that gene conversion resulting from DNA repair resulting from adaptation to (desiccation in) its environment may provide enough of the advantages of sex that bdelloids can survive,” Mark Welch says.

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Genetic link tied to smoking addiction

Scientists have pinpointed genetic variations that make people more likely to get hooked on cigarettes and more prone to develop lung cancer - a finding that could someday lead to screening tests and customized treatments for smokers trying to kick the habit.

The discovery by three separate teams of scientists makes the strongest case so far for the biological underpinnings of nicotine addiction and sheds more light on how genetics and lifestyle habits join forces to cause cancer.

"This is kind of a double whammy gene," said Christopher Amos, a professor of epidemiology at the M.D. Anderson Cancer Center in Houston and author of one of the studies. "It also makes you more likely to be dependent on smoking and less likely to quit smoking."

A smoker who inherits these genetic variations from both parents has an 80 percent greater chance of lung cancer than a smoker without the variants, the researchers reported. And that same smoker on average lights up two extra cigarettes a day and has a much harder time quitting than smokers who don’t have these genetic differences.

The researchers disagreed on whether the variants directly increased the risk of lung cancer or did so indirectly, by causing more smoking.

The three studies, funded by governments in the U.S. and Europe, are being published Thursday in the journals Nature and Nature Genetics.

The scientists studied the genes of more than 35,000 white people of European descent in Europe, Canada and the United States. Blacks and Asians will be studied soon and may yield different results, scientists said.

They aren’t quite sure if what they found is a set of variations in one gene or in three closely connected genes.

The gene variations, which govern nicotine receptors on cells, could eventually help explain some of the mysteries of chain smoking, nicotine addiction and lung cancer. These oddities include why there are 90-year-old smokers who don’t get cancer and people who light up an occasional cigarette and don’t get hooked.

"This is really telling us that the vulnerability to smoking and how much you smoke is clearly biologically based," said psychiatry professor Dr. Laura Bierut of Washington University in St. Louis, a genetics and smoking expert who did not take part in the studies. She praised the research as "very intriguing."

The smoking rate among U.S. adults has dropped from 42 percent in 1965 to less than 21 percent now.

The new studies are surprising in that they point to areas of the genetic code that are not associated with pleasure and the rewards of addiction.

That may help explain why some people can quit and others fail, said Dr. Nora Volkow, director of the National Institute of Drug Abuse in Bethesda, Md., which funded one of the studies.

"It opens our eyes," Volkow said Wednesday. "Not everyone takes drugs for the same reason. Not everyone smokes cigarettes for the same reasons."

One clue is in the location of the just-discovered variants, on the long arm of chromosome 15, Volkow said. It is in an area that, when damaged during tests on animals, makes them depressed and anxious. While some people smoke because it helps them focus or gives them a physiological reward, others do it to stave off depression.

That suggests that adding antidepressants to some smokers’ treatment could help them kick the habit.

Bierut said a simple, inexpensive test could be developed to screen people for the variants. Kari Stefansson, lead author of the largest of the three studies, agreed. He is chief executive of deCode Genetics of Iceland, which already does prostate cancer genetic tests.

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