Cancer is a numbers game. Larger, longer-lived animals with more cells should get more tumors than do small, short-lived animals. And yet mice are more susceptible to cancer than we are. Now, a new study offers a tantalizing explanation. The genomes of smaller mammals contain more viruses, which the authors suggest may account for their higher rates of cancer.
Aris Katzourakis, an evolutionary biologist at the University of Oxford in the United Kingdom, didn’t set out to explain rates of cancer in animals. He was interested in why over the last 10 million years the genomes of mice have accumulated 10 times more small RNA viruses, called endogenous retroviruses (ERVs), than has the human genome. He teamed up with researchers from Plymouth University and the University of Glasgow in the United Kingdom to mine for retroviruses in the genomes of a range of mammals—including shrews, humans, dogs, and dolphins. The researchers then tested whether differences in how long mammals live and in how quickly they mature affects how many ERVs they harbor.
By the time the team had identified more than 27,000 unique viral sequences across 38 different mammals, it saw a clear pattern emerging: Small mammals have more ERVs than do larger ones. Mice have more than 3000, whereas dolphins have just 55, and humans are somewhere in the middle with 348, the researchers report online today in PLOS Pathogens.
Larger animals have many more cells, and should therefore have more of these endogenous retroviruses. That they have fewer means they must have found efficient ways to remove them, Katzourakis says. That suggests ERVs can be harmful to their hosts, and this harm is more costly, in an evolutionary sense, to large animals.
How do ERVs harm their hosts? Katzourakis suspects that some ERVs cause cancer. The viruses embed in an organism’s genome and make copies of themselves, and these duplicates then split and reinsert randomly at different locations in the genome. More often than not, these viruses do no harm, but occasionally their reinsertion transforms a healthy cell into a cancerous one. One such event led to the untimely death of the world’s first cloned sheep, Dolly, who succumbed to lung cancer caused by the Jaagsiekte sheep retrovirus. Katzourakis proposes that the higher number of ERVs in small-bodied animals may account for their higher rates of cancer.
“It’s nice to see real experimental results that can help explain the vast differences in cancer susceptibility per gram of tissue between small, short-lived animals and large, long-lived animals,” says epidemiologist Richard Peto of the University of Oxford, who was unconnected to the new study. He first recognized the unexpected differences in cancer susceptibilities between animals of different body sizes in the 1970s, an observation that became known as “Peto’s Paradox.”
From an evolutionary perspective, Peto explains, it makes sense that larger animals are better at protecting their genomes from potentially cancer-causing viruses. Large animals tend to live longer and reproduce later, so it is more important for them to postpone the onset of cancer.
Although the findings pinpoint one mechanism underlying the vast difference in cancer rates, they don’t explain all cancers, says George Kassiotis, a virologist at the National Institute for Medical Research in London who studies ERVs in humans and mice. Despite having few ERVs, he explains, humans still get cancers. ERVs are therefore likely to be one of many factors contributing to cancer rates. “One important aspect of this new study is that it provides a framework to quantify the contribution of ERVs to cancer,” he says, “which in turn will inform the contribution of other causes of cancer.”
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The Experimental Lakes Area (ELA), Canada’s flagship environmental research center that has been under threat of closure for 2 years, has found a savior. The ELA will leave government hands and will now be managed by the International Institute for Sustainable Development (IISD), a Winnipeg-based think tank. The 1 April announcement guarantees that the 46-year-old field site in northwestern Ontario will survive, at least for another 5 years, and will expand its research focus beyond that of the Canadian government’s mandate.
The deal will hopefully bring the ELA some “stability,” says Diane Orihel, a freshwater ecologist who since mid-2012 has led a campaign to save the facility. The campaign began after the Canadian government pulled the project’s funding and handed pink slips to its team of 16 scientists and technicians. Last year, the lab, which conducts experiments in a system of 58 lakes, was saved from the bulldozers by a stopgap payment of $2 million from the provincial government of Ontario. Now, IISD has a chance to rebuild the ELA after years of neglect by the Department of Fisheries and Oceans, Orihel says.
The ELA, the world’s only facility where researchers can intentionally poison whole lakes to monitor ecosystem effects, has an impressive research record: Its scientists were the first to find evidence for acid rain, and to fully diagnose the effects of pollutants such as mercury, phosphate, and synthetic hormones on aquatic life. IISD President Scott Vaughan tells ScienceInsider that he intends to build upon this past research, while looking to expand the scope of the facility’s science to investigate the effects of micropollutants and climate change on aquatic systems.
The takeover deal relies on agreements between Ontario and IISD, between Canada and IISD, and a third trilateral Canada-Ontario-IISD pact to ensure that all long-term data and physical samples from the facility are available to future researchers. Access to these freshwater data sets—some of the longest and most thorough in the world—will keep scientists coming back to ELA, backers say.
But the fresh management brings new challenges. The provincial government of Ontario has pledged $2 million a year for 5 years to cover operating costs and long-term monitoring. These funds will be topped up by Manitoba and Canada, which have promised $900,000 over 6 years and $250,000 per year for 4 years, respectively. But the provincial and federal moneys will not fund scientific experiments, which were previously funded through government grants. ELA scientists will now need to partner with universities to apply for those national grants. And beyond the next 5 years, the IISD will need to embark on a major fundraising campaign to keep the ELA open. “That’s an ambitious amount of money to raise,” Orihel says.
The next challenge will be to staff the facility. Vaughan says his goal is to invite back the scientists who previously worked at the ELA and offer them a job with IISD. That will be difficult, Orihel says: “The science team has been withering away for a number of years; as people retire they haven’t been replaced … some scientists got frustrated and took other positions.” She adds that the ELA is not just buildings and lakes, it is people, and the government should have done more to transition that previous team to a new operator.
If a new team can be found in time, the takeover comes just in time for experiments at the facility to resume in the spring. And this summer, after consultations with interested university-based scientists, the new research plan will be announced.
Brokering the deal has been a long haul, Vaughan says. IISD members are “incredibly grateful” to the scientists, including Orihel, who worked to save the ELA before IISD stepped in. He adds: “They are an impressive group of committed scientists.”
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LONDON—The votes are in, and the top prize in a contest to redesign a bust of Charles Darwin goes to a floating crocheted head of the eminent naturalist created by Cristina Amati, a graduate student at University College London (UCL). The contest, whose winner was announced today to mark the 205th anniversary of Darwin’s birth, was set up by UCL to fill a void created by the relocation of the original bust of the naturalist. Along with the winner, the empty pedestal inspired six other zany sculptures depicting the famed naturalist, which include his face fashioned from the pages of his seminal book, The Origin of Species; a likeness molded from transparent nutrient-enriched gel through which ants will be enticed to tunnel; and an inch-tall bust containing a USB flash drive. The competition’s seven entries—on display in a 7-week-long exhibition at the Grant Museum of Zoology in London, starting on 12 February—are all based on 3D scans of the original plaster bust.
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A measleslike virus appears to be the chief cause of the droves of dead dolphins that have washed ashore along the Eastern Seaboard of the United States this summer, researchers announced yesterday. Since 1 July, 333 bottlenose dolphins have been recovered from beaches between New York and North Carolina—10 times the number usually recovered at this time of year.
In early August, the large number of strandings prompted the National Oceanic and Atmospheric Administration (NOAA) to declare an Unusual Mortality Event. The declaration freed up federal funding to assist NOAA’s Marine Mammal Health and Stranding Response Program to retrieve and assess the mammals’ remains. The results of their investigation point to a type of morbillivirus as the cause of the die-off—a group that includes viruses that cause measles in humans and distemper in dogs.
The team’s detective work combined traditional techniques that examined tissues from dead animals’ lungs, brains, and lymph systems with molecular techniques to probe for the presence of the virus. So far, researchers have examined 33 dolphins; 32 have tested positive for morbillivirus. Genetic sequencing has confirmed that 11 carry the type of morbillivirus that infects only dolphins, porpoises, and whales.
“Along the Atlantic seaboard this [outbreak] is extraordinary; this is the largest outbreak that we have had since the 1987 die-off,” said Teri Rowles, head of NOAA’s Marine Mammal Health and Stranding Response Program, in a teleconference with reporters. Morbillivirus was also responsible for a devastating 1987 die-off which killed more than 700 dolphins.
Many wild dolphins exposed during that epidemic probably developed immunity to the virus, Rowles says. But a population’s immunity is slowly eroded over time; animals born since 1987 are probably susceptible, Rowles says.
The virus may have taken hold when the dolphin population reached a tipping point, with enough susceptible individuals to sustain its spread, says veterinary epidemiologist Stephanie Venn-Watson of the National Marine Mammal Foundation in San Diego, California. The epidemic will continue until the number of susceptible animals dwindles, researchers predict. There is no feasible way to vaccinate or treat the animals, they add.
It is difficult to predict how many bottlenose dolphins will ultimately succumb to the disease, and the documented strandings probably represent just a fraction of the infected animals. It is also not clear whether the virus will spread to other dolphin species. Typically, morbillivirus strains don’t spread beyond closely related species, researchers say.
As for any threat to people, “there is no indication that this virus could jump into humans,” says virologist Jerry Saliki of the University of Georgia in Athens. However, morbilliviruses suppress the immune system, so many of the washed-up animals are sick with secondary bacterial infections that are communicable to other mammals. Under some circumstances, rotting carcasses could pose a threat to beachgoers and other mammals.
NOAA plans to continue to monitor the spread of the infection and investigate whether marine pollution could be worsening the impact of the outbreak. Rowles explains that high levels of polychlorinated biphenyls, or PCBs, known to suppress mammals’ immune systems, have been reported in some areas along the eastern coastline. “We will be monitoring those areas very closely,” she adds.
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U.K. researchers are going to have live with a flat R&D budget over the next few years. But on a day when British finance minister George Osborne announced a series of painful belt-tightening budget measures, observers say that the outcome for science could have been worse.
“In a difficult Spending Round, at a time of great economic challenge, we congratulate [Osborne] on maintaining investment in science and research,” said Ted Bianco, acting director of the Wellcome Trust, in a statement. Others were less optimistic. The flat R&D budget “adds real risk and difficulty,” warns Mark Downs, chief executive of the Society of Biology.
In a 26 June speech in London, Osborne said that the 2015 and 2016 science budget will be set at £4.6 billion a year—a level it hasn’t budged from since 2010. However, new money will be freed up for science infrastructure: a cool £1.1 billion a year until 2016 that nearly doubles the capital spending earmarked in the last spending review. The “huge investment” from the Department for Business, Innovation and Skills recognizes the enormous strength science brings to the modern economy, Osborne declared.
Handed lemons, the country’s top scientists are courageously making lemonade. In light of steep cuts that other government agencies must absorb, a stable R&D budget “is excellent news for the whole science community and we look forward to hearing how the investment will be used to meet the needs of our world-leading research teams,” said Peter Knight, president of The Institute of Physics in London, in a statement. Lesley Yellowlees, president of the Royal Society of Chemistry in London, added that the investment is proof that the government has heeded the science community’s calls for protecting research.
After the government’s comprehensive spending review slashed science infrastructure spending by 25% in 2010, British science has had to make do with piecemeal funding for major initiatives such as high performance computing, synthetic biology, and advance materials. The new spending document offers a call out to “high-priority projects” such as the Synergistic Air-Breathing Rocket Engine, a hypersonic, precooled engine for the United Kingdom’s new spaceplane, and a supercomputer for weather forecasters.
Rules require that capital funds are spent on hardware or bricks and mortar, not on research. Because the budget allocated by research councils for R&D isn’t going up while inflation is, that means fewer and smaller grants will be awarded in 2015 and 2016. The review also leaves the United Kingdom languishing in seventh place among G8 nations in R&D spending as a proportion of gross domestic product (GDP); its 0.6% tops only Italy. “A commitment from all sides of the debate to raise total government investment in science to the EU average of 0.7% of GDP, by the end of the next Parliament, would set Britain on the path for science-fuelled growth,” Yellowlees said.
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Women who have beaten the odds to find themselves in the upper echelons of science face a further hurdle—visibility. Female scientists are less likely to sit on science advisory boards, receive awards, and give invited talks at conferences. However, a new study suggests that the reasons women appear less often on the podium are complicated.
Reporting in the Journal of Evolutionary Biology, Julia Schroeder of the Max Planck Institute for Ornithology in Germany and Hannah Dugdale of the University of Sheffield in the United Kingdom found that only 16% of invited speakers at the European Society for Evolutionary Biology Congress between 2001 and 2011 were women. The total—66 of 430 individuals—was half of what would be expected based on the number of senior female scientists in the life sciences.
The dearth of women is not because they aren’t being invited. Instead, female scientists were twice as likely as their male counterparts to turn down an invitation to talk in slots reserved for presenting original and important work. At the same time, the number of female presenters of posters and uninvited talks was almost at parity with men.
Evolutionary biologist Trudy MacKay of North Carolina State University in Raleigh says that relatively short notice and a tight budget contributed to her decision to decline an invitation to talk at the congress in 2011. Women also turn down talks because they receive too many invitations each year and are anxious about balancing the demands of family and work, says Jeanine Olsen of the University of Groningen in the Netherlands, who headed one of Europe’s Seventh Framework Programme’s Gender Action Plans aimed at promoting gender awareness. Younger women also tend to do less self-promotion, Olsen adds.
Finding ways to address those issues is next on Schroeder and Dugdale’s agenda. And the first step is to contact scientists to find out why they declined invitations. “Then we [will] know what can be done to change their minds,” Schroeder says.
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GUELPH, CANADA—When plucking a snail from the beach you’d be lucky to snag a left-coiling shell. That’s because only 5% of all snails are “lefties,” new research shows. Shell enthusiasts have long marveled at the lack of sinistral (left-coiling) snails among their collections, especially when other shelled mollusks, such as clams and the now-extinct ammonites—nautiluslike creatures that sported dozens of tentacles inside spiraled shells—are just as likely to be left- as right-coiling. Now, in the largest survey of its kind, researchers inspected more than 55,000 snail species—representing two-thirds of all gastropods—to reveal that left-coiling has arisen more than 100 times, and yet few of the species that have made the switch have been particularly successful. In the rare cases where left-coiling took off, it was almost always on land, the team reported here in a presentation last week at the annual meeting of the Canadian Society of Zoologists. The researchers don’t know why sinistrality is so rare underwater, but the most likely explanation, they say, is that unlike land snails that tend to hang around where they hatch out, the microscopic young of sea snails are carried on ocean currents that make the chance of meeting and reproducing with another left-coiling nest-mate slim. Without such a meeting, the left-coiling lineage goes extinct.
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TORONTO, CANADA—German scientists have pulled out of an international research project with Canada that was attempting to find ways to minimize the environmental damage caused by exploiting Alberta’s oil sands. The move comes after political pressure forced Germany’s largest scientific organization, the Helmholtz Association of German Research Centres, to rethink its connections with an industry that many consider to be environmentally destructive.
The scientists who are part of the Helmholtz-Alberta Initiative (HAI) will no longer be involved in developing technologies that improve Alberta’s crude oil or treat the toxic effluent from the oil sands projects. Instead, the scientists will focus their efforts on the initiative’s remaining research avenues, such as carbon capture and storage and mine site reclamation.
It is a change in focus, Stefan Scherer, the managing director for the HAI, tells ScienceInsider. HAI, founded in 2011, is a partnership between the Helmholtz Association and the University of Alberta “designed to find solutions to the pressing environmental issues facing energy projects such as Alberta’s oil sands in Canada and coal production in Germany,” according to the project’s Web site. “I don’t anticipate laying off scientists,” nor will money be withdrawn from the project; the initiative is not collapsing, Scherer adds. That sentiment was echoed by a spokesperson for Alberta’s Environment Minister Diana McQueen, whose department donated CAD $25 million to the project 2 years ago.
Of the four Helmholtz institutes involved in the partnership, only one, the Centre for Environmental Research (UFZ) in Leipzig, has suspended its work in Canada. The institute’s supervisory board voted in December to impose a moratorium on UFZ’s involvement in the project. This decision is a “small hiccup”, explained Lorne Babiuk, the vice president of research at the University of Alberta and co-chair in the initiative. He added that the initiative’s focus can easily be redirected because much of the technology being developed for use in the oil sands is relevant to other carbon industries. “We will reorient the initiative,” agrees the other co-chair, Reinhard Hüttl, scientific executive director of Helmholtz Centre Potsdam. “We won’t have projects directly related to oil sands.”
The German move was in part triggered by ongoing debate over a possible amendment to the European Union’s fuel quality directive that would restrict the use of “high-polluting” oil within Europe. Germany, the largest market for fuels in Europe and the fourth largest in the world, has so far blocked the move along with the United Kingdom, but public opposition to importing Albertan oil remains high. The Canadian government has been lobbying German politicians at both the national and the European level to continue blocking the ban. That lobbying, along with Canada’s withdrawal from the Kyoto Protocol, prompted several German politicians to ask the Helmholtz Association pointed questions about the Alberta project.
“It was seen as a risk for our reputation,” Frank Messner, Helmholtz’s Environmental Research Centre head of staff, told a European news Web site. “As an environmental research centre we have an independent role as an honest broker and doing research in this constellation could have had reputational problems for us, especially after Canada’s withdrawal from the Kyoto Protocol,” he said.
An independent assessment into Helmholtz-Alberta Initiative environmental credentials will report its findings in June.
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