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June 30, 2006

Indian Ocean tsunami warning system plugged in

Alerts can now be issued to governments, but will the word get to the people?

Eighteen months after a deadly tsunami killed more than 200,000 people in the region, a tsunami early warning system for the Indian Ocean is now up and running.

Read the story here.

June 29, 2006

Plastics get fruity

Sugar can provide the raw materials for polystyrene.

Apple juice and corn, rather than petroleum, could be the raw materials for some of the plastics and pharmaceuticals of the future, thanks to a new chemical process devised by researchers at the University of Wisconsin in Madison.

Read the story here.

Bushmeat surveyed in Western cities

Illegally hunted animals turn up in markets from New York to London.

Baboons, duiker antelopes and cane rats are available by the pound in markets in major cities in North America and Europe, a scientist reported at the Society for Conservation Biology meeting in San Jose, California, this week.

Read the story here.

SCB: Goodbye

Well, another SCB has come to a close. Next year's meeting is in Port Elizabeth, South Africa, and the theme is "One World, One Conservation, One Partnership" http://compworx.isat.co.za/scb/. I hope to see you there.

SCB: Conservation classifications

Okay, so Nick Salafky's big idea isn't just his, but a whole bunch of people who have been meeting and meeting and meeting to hammer out one standardized vocabulary to describe the conservation problems and solutions. He described it as "so unsexy", but so important. The idea is, that if you are a conservationist describing a bit of land being threatened by overgrazing, you could describe that problem as "cows" or "cattle" or "grazing" or "overgrazing" or any number of other words. But if everyone uses the same words, suddenly everyone can work off of the same checklist, can summarize their site in just a few simple words, and search databases and journals effectively for similar issues.

The cooperating groups are the IUCN and the CMP, and the new classifications are available at www.conservationmeasures.org. This August, at the first European Congress of Conservation Biology, a symposium will put this idea together with two others that have as their aim the rigorization (to coin a word) of conservation. You can read about the two other ideas here.

SCB: Need for speed

This year the SCB tried out a new presentation format, modeled off speed dating. In the first half of the session, each presenter got 3 minutes to present their work, and in the second half, everyone milled around chatting with those presenters whose work intrigued them.

Personally, I felt that it was a brilliant format. Three minutes really is enough to convey the bottom line, everyone got their questions in, and lots of real back and forth dialogue seemed to be going on. Certainly, business cards and so forth were flying about, and the noise level of the room was a happy din.

One particularly odd moment came when Guillermo Andres Ospina, rather than trying to cram everything about his project into three minutes in a second language, simply presented all the slides from his full-length talk on "Biodiversity conservation under armed conflict in Colombia" quickly, in silence, one after another. I must say, it felt very futuristic, as if we were all absorbing all the words and images flashing on the screen with wiser, more powerful brains.

The speed presentation idea was cooked up by four people, including bow-tied conservation gadfly Kent Redford, who told me the idea owed its birth to the concept of the remote control. One other co-inventor, Nick Salafsky, introduced his talk by explaining that the three minute time limit appealed to him because he felt his topic was so dull. Actually, I thought his topic was pretty interesting, and I just might write my next post on it.

June 28, 2006

Science on the solstice

Every day, all over the planet and beyond it, scientists try and make sense of the world in which they live. In this special feature we present a composite picture of just one of these days -- June 21 2006, the summer solstice. In over a hundred entries, ranging from mountain tops to the middle of the ocean, from pregnant seahorses to clocks made of light, all scientific life is here.

Read more here

Crops could make their own fertilizer

Plants that build homes for bacteria could do without chemical nitrogen.

Plant geneticists have induced plants to form 'fertilizer factories' without the aid of bacteria that are normally crucial to the process. If the technology can be transferred to plants such as wheat or rice, industrial fertilization of these crops could be reduced or even abolished.

Read more here

Human eggs supply 'ethical' stem cells

Work with unfertilized eggs could provide a way around restrictions on embryo experiments.

Human embryonic stem-cell lines have been successfully produced without using fertilized eggs. The researchers responsible work in Italy, which has some of the most restrictive embryo-research laws in the world. They hope the work will be welcomed as an ethically acceptable source of stem cells, as it does not involve destroying a viable embryo.

Read more here

Nature Insight -- Stem Cells Podcast

Twenty-five years after stem cells were first identified in mice we can now isolate and grow stem cells from humans, opening up potential therapies for diseases such as Parkinson’s and diabetes. But with these opportunities comes ethical controversy and claims of fraud in some stem-cell research fields.

This special Stem Cells Podcast presents interviews with leading stem cell researchers and a live discussion on the various scientific and ethical problems in this highly charged arena.

LISTEN to the show now and join the discussion!

Nature Podcast 29 June

On this week's Nature Podcast we circumnavigate the globe and investigate science around the world on the summer solstice. We also discover self-repairing brains, black holes, how to choose the right cleaner fish, construct the new germanium, sample ecosystem stability, and tuck into prion diseases.

Listen to the show and tell us what's on your mind.

To SUBSCRIBE for FREE to the Nature Podcast copy and paste this URL into iTunes or your preferred media player.
http://www.nature.com/nature/podcast/rss/nature.xml

SCB: Screen vs. green

I hesitate to write this next item, as it may well make you turn off your computer and put on your hiking boots. Patricia Zaradic of the University of Illinois has found an eerily tight correlation between a decline in attendance at US National Parks since 1987 and the rise of electronic entertainment: movie rentals, video games, and our friend the internet. Oil prices fit well too. So, although it is just a correlation, one can easily make up a story about a nation of people who can't afford to drive to parks, who are turning away from nature and towards screens.

Like many of the findings being presented here, this is pretty depressing news. Nature is being whittled away and no one cares much, because, well, we can always use computers to generate images of nature if we need them. The silver lining, I guess, is that if fewer people are going to National Parks, they are bound to be less crowded.

SCB: Pristine wilderness?

Here's an interesting story. John Neidel from Yale went to Kerinci Seblat National Park on Sumatra, a supposedly pristine wilderness. There are two villages inside the park, accessible only by foot, which, according to Neidel, are generally seen by conservationists as encroachments. Neidel did a bit of poking around, and found something like 40 former village sites, some with evidence of moats around them, some with large stones. Some of the villagers have documents supporting their residency that go back to the seventeenth century.

Neidel's take seemed to me to be that there is an underlying bias in conservation circles towards this "pristine wilderness" idea. It seems that evidence of long-term habitation by villagers was overlooked or ignored in the efforts to save the forest there. "instead of the people encroaching on the national park, one could say that the national park is encroaching on them," he said.

SCB: Elephant noises

Here's an update on interesting research trying to a get a handle on the number of forest elephants (Loxodonta cyclotis) in Africa. These animals, which are smaller and thiner-trunked than savannah elephants, live beneath trees, so are harder to count. But they do make noisel—low deep rumbles that travel great distances. Once it was determined that the elephants call at a fairly constant rate, researchers at Cornell began counting the calls to estimate of the number of animals.

Nature has written about this neat project before: here. Mya Thompson, a graduate student on the project, told me that they are working on funding to use the equipment to detect more sinister sounds: gunshots, chainsaws—the sounds of illegal logging or poaching. The ultimate idea is to equip their stations with the means to alert the authorities when one of these suspicious sounds is recorded.

June 26, 2006

SCB: Babbitt's Mad

Former US Secretary of the Interior Bruce Babbitt spoke to the SCB last night (he's flogging a new book). Now "free at last to say what I think" he took the Army Corps of Engineers to task for their plan for restoring the sinking Louisiana coast, which can be found here. To be fair, this plan was completed before Hurricane Katrina, but Babbitt claims that its estimate of how much land will be lost is way off, because it assumes that land-loss rates from the seventies through 2000 will continue in the future.

The ACOE plan estimates that Coastal Louisiana will lose 328,000 acres by 2050. Babbitt says that he figures that subsidence and sea level rise (thanks to our pal global warming) will submerge some 6 million acres by 2100. Even assuming that New Orleans is safely walled off, he says that a million people "are in grave risk of floating by the end of the century."

Then he took the conservation community at large to task for taking the ACOE study seriously. "The most charitable explanation is that we—I mean all of us…tend to operate in a climate of political intimidation," in which telling hard truths about very large scale problems is not the done thing.

"We risk undermining our credibility by going along with these kinds of analysis," he said.

SCB: Binge and Purge

The other side of inbreeding

Inbreeding is generally regarded as bad for species, if not downright icky. But something called "purging" has sometimes been invoked to explain why some populations squeeze through a bottleneck and blossom on the other end with few problems. Now some fly experiments have confirmed the power of purging – at least in the lab.

[click on for more]

Inbreeding is generally regarded as bad for species, if not downright icky. But something called "purging" has sometimes been invoked to explain why some populations squeeze through a bottleneck and blossom on the other end with few problems. Now some fly experiments have confirmed the power of purging – at least in the lab.

When only a small number of animals remain in a population, there is always a worry that inbreeding will bring out unpleasant recessive genes. The reduction in the reproductive vigor of an inbred population is called "inbreeding depression" by conservationists. But not all species seem to show it to the same extent.

"We can have populations that lack genetic diversity and do not seem to show a decrease of fitness," says Juan Bouzat, who presented the experiments today at the Society for Conservation Biology meeting in San José, California. An example of this is the Northern Elephant Seal, which passed through a very tight bottleneck due to hunting, and now seems fine. The common explanation, according to Bouzat, is that this is because of a "purging" of the bad genes by natural selection.

Here is how purging is thought to work: in inbreeding, the chances of two copies of a deleterious gene showing up increase, and those recessive genes that have been quietly hanging out in the population emerge to be acted on by natural selection. If they are deleterious enough, they will doom the animal and become "purged" from the population. If this happens to a population, then the next time they are put though a bottleneck, there will be fewer bad recessives to show up and decrease the animals' fitness. The prediction is, therefore, that a history of inbreeding will make a species better able to pass through another genetic bottleneck without going extinct.

Bouzat, a biologist at Bowling Green State University in Ohio and William Swindell, his student, put this idea to the test by breeding two populations of fruit flies caught in an orchard in Bowling Green. One population they put through a bottleneck, they other they did not. Then, in each population, they measured how much worse off the offspring of siblings were than the offspring of unrelated individuals.

Their key result was that populations that had never been inbred had a much worse time when forced to breed with their siblings—they produced far fewer viable offspring. In the group that had been inbred , a sibling match was still less successful than a random one, but not as dramatically so. It was as if, having shed some unpleasant genetic baggage during their former period of inbreeding, there was less to go wrong.

So "inbreeding depression" may not effect all species equally. "In reality," says Bouzat, "different species may have different probabilities of going extinct , depending on their inbreeding history."

University of Vermont population geneticist Charles Goodnight says the result is important for conservationists. "If you have a species forced to a very small size , if you keep the population safe and viable through the risky inbreeding depression period, it could improve in the end."

References
1. Swindell, W & Bouzat, J. Journal of Evolutionary Biology. 19 (1257-1264). 2006
2. Swindell, W & Bouzat, J. Evolution. 60 (1014-1022) 2006.

SCB: Football and a Flamingo

At this meeting, it is a pure pleasure to hear about some tiny bit of our beleaguered globe in which the environment is improving. In this case, according to Elizabeth Heise of the University of Texas at Brownsville, we have the Texan passion for high school football (the US kind, naturally) to thank.

Bahia Grande means Grand Bay, but the Bahia Grande, which is near the mouth of the Rio Grande on the East coast of Texas, has, since the 1930s, been more like the Desierto Grande—dammed dry and grazed to nothingness. This great expanse of empty land became the source of huge amounts of airborne dust, which reduced visibility on the football field of nearby Port Isabel High School. So, "the largest wetland project is United States history" according to UT Brownsville, was undertaken.

10,000 acres were re-flooded a year ago, and now it is filled with invertebrates, fish, birds, and native plants planted by students. Heise showed a picture of a flamingo that fished there for several weeks this year. She hopes it will return next year, as it brought them an awful lot of good press. Go Port Isabel Tarpons!

June 25, 2006

SCB: Buzz, Beards and Two Buck Chuck

The opening reception for the SCB featured a whole lot of people doing interesting things, from modeling the date that the mammoths went extinct to fishing in Maine to determine which species of fish's gills are home to freshwater mussel larvae. There were hints of good sessions to come, particularly one on "Advocacy in Conservation Science", which will try to answer the question of whether Conservation Biology and its journals should explicitly endorse various policy options ("we should remove Dam X") or just present the science (If we remove Dam X, this or that will likely happen"). This is interesting stuff. After all, the very name "Conservation Biology" contains an implied bias: things ought to be conserved. In a way, it is unique. One doesn't hear about a discipline called Let's Go To Mars Space Science.

Hot topics included whether or not the ivory billed woodpecker is extinct or not, the usefulness—or not—of the "biodiversity hotspot" concept, and whether US conservationists are good at math. As usual for the SCB, dress was distinctly, even defiantly casual, beards and sandals were in abundance, and small children and babies were well represented: a laid-back vibe concealing a whole bunch of smart and passionate nature geeks. Good people, in other words.

On the other hand, a glass of Charles Shaw wine, a whole bottle of which one may purchase at Trader Joe's in most parts of the US for two or three dollars (thus, "Two Buck Chuck"), was running $5.75. Boo.

Brain can be made to self-repair

Triggering stem-cell growth could help brain recover after a stroke.

Stimulating a protein on the surface of the brain’s stem cells helps rats recover after a stroke, US researchers have found. The discovery suggests that in humans it could be possible to provoke the body’s own stem cells into repairing an injury, rather than laboriously growing and transplanting new cells.

Read more here

Society for Conservation Biology – First Blog Entry

This year's assemblage of conservation biologists takes place in San José, California (frequently written without the accent), which lies at the Southern end of San Francisco Bay. It is divided from the Pacific Ocean by a series of hills which stop ocean moisture. So, here it is hot and, from the air, a burnt grass colored landscape surrounds the city. Formerly an agricultural town—its seal features a plump bouquet of wheat—it is now part of Silicon Valley, that famed US home of high tech.

The theme of the conference is "Conservation Without Borders" so expect to hear the latest about geographical, organizational, political and disciplinary blurring of all kinds. Stay tuned…

June 23, 2006

CJD-related disease can incubate for 50 years

Last living cannibals aid predictions for modern prion epidemic.

People in Papua New Guinea who once feasted on their own relatives succumbed to prion disease as much as half a century later, say scientists who have laboriously tracked down the last sufferers in remote villages.

Read more here

Mature sperm and eggs grown from same stem cells

Technological advance could help infertile people to have children.

Stem cells from a mouse embryo have been coaxed into producing both eggs and sperm in the same dish. The eggs and sperm are the most mature yet grown in the lab, and the advance brings researchers closer to their ultimate aim: producing human eggs and sperm from adult body cells so that infertile men and women can have their own children.

Read more here

June 22, 2006

Brain ‘traffic jams’ drive Parkinson’s symptoms

Stopping cellular tailbacks could speed the way to therapies.

Using a zoo of animals from yeast to rats, US scientists have shown that speeding the flow of proteins in cells might relieve one of the underlying causes of Parkinson’s disease.

Read more here

Oldest known jewellery discovered

Beads made from shells represent earliest personal adornment.

It can take hundreds of beads to make a single bracelet, and thousands for a haute couture gown. But it has taken only three shell beads to shake up our theories about human evolution.

Read more here

Magnets zap migraines

Headache pills might be superseded by portable device.

Migraine sufferers might soon be able to block an imminent attack using a device that targets the brain with a powerful magnetic field.

Read more here

June 21, 2006

Fussy fish prefer trustworthy cleaners

Sea bream choose cleaners they’ve already spied hard at work.

It turns out that even for a fish, eavesdropping might help in figuring out who you can trust not to stab you in the back. The sea bream Scolopsis bilineatus apparently spies on cleaner fish Labroides dimidiatus before deciding which of them to employ.

Read more here

Southern California due major earthquake

Large buildup of strain in the San Andreas fault makes quake imminent.

Southern California could be in line for a serious quake along the infamous San Andreas fault, seismologists have found. New measurements suggest that the region close to Los Angeles, the traditional earthquake location in Hollywood disaster movies, could feel the effects of a real-life tremor within the next few years.

Read more here

Womb transplants ‘in five years’

Successful sheep trial raises hopes for human procedure.

Womb transplants in humans should be possible within five years, say scientists in Sweden who have successfully transplanted uteruses in sheep. The procedure would allow women who have functioning ovaries but no womb to carry their own children, and the researchers say they have already been contacted by hundreds of women who are interested in having such a transplant.

Read more here

Hawking rewrites history... backwards

To understand the Universe we must start from the here and now.

How did the Universe begin? Many scientists would regard this as one of the most profound questions of all. But to Stephen Hawking, who has perhaps come closer than anyone to answering it, the question doesn’t in fact even exist.

Read more here

ESHRE: Cutest baby pic

Nearly every talk I've attended at this conference has included at least one slide showing a smiling bouncing baby, to remind us all why ultimately we're here, I guess.

But the prize for the most gratuitously cute pic of the meeting has to go to Jacquetta Trasler of Montreal Children's Hospital Research Institute, during her (very informative) talk on genomic imprinting. Most of the work has been done in mice, not humans. So she illustrated it with a photo of tiny newborn twins peeking out of a pair of boots, each complete with fluffy mouse ears. It's enough to make even a hardened science journalist broody.

ESHRE: To screen or not to screen?

I went to a fascinating session on pre-implantation genetic screening (PGS) this morning. That's where a cell is taken from the early embryo during IVF, and screened for chromosomal abnormalities before it is implanted into the mother.

It's used mainly for couples seen as at high risk of chromosomal problems, for example if the mother is old (say 38 or older), or if she has had recurrent miscarriages.

Leeanda Wilton of Melbourne IVF gave a great presentation on the technologies available so far. In the past the screening has been done using a technique called FISH -- where fluorescent probes of different colours check for the presence of certain chromosomes in the cell. Only 5-9 chromosomes can be screened this way though, and she's done work to show that this does let through embryos that have problems in other chromosomes. She and her colleagues are pioneering a method called comparative genomic hybridisation (CGH), where the whole genome is screened. DNA from the embryo cell and from a normal test cell (one dyed green, one dyed red) are washed over the chromosomes from a normal cell and by looking at the relative amounts of red and green you can make sure that the correct amounts of each part of the genome are present in the embryo.

That takes a few days though, so you have to freeze the embryo while you wait for the results. Now she's working on doing the hybridisation on microarrays, which is much quicker, and much more accurate (I mentioned this idea in a news story on Monday, see http://www.nature.com/news/2006/060612/full/060612-16.html). "We're moving towards having an almost off the shelf DNA chip on which you could analyse anything that turns up," she said. "These are very exciting times."

One member of the audience pushed her on the problem that many embryos are mosaic at the 8-cell stage - in perhaps 60-70% of them different cells can have different complements of chromosomes. So if you're just taking one of those cells for screening, how can you be sure it will be representative?

Wilton admitted this is a problem that can't be sidestepped. But she says that when her group has looked at all the cells in an embryo, she reckons they would only have made the wrong decision about whether to keep or trash an embryo only about 5% of the time.

Excitement was tempered further by a talk by Catherine Staussen, from the Dutch-speaking Free University of Brussels. She's been looking at clinical trials that have tried to test whether PGS actually improves the success rate of IVF. Unfortunately the data are few and far between. But based on what is available, she concludes that there is no evidence to support that idea that screening improves a woman's chance of having a healthy baby. She gave several possible reasons for that - perhaps the current methods aren't screening enough chromosomes (the trials only looked at the FISH technique). Perhaps PGS is having an adverse effect on the tested embryos, that cancels out any benefit from the screening. Perhaps as the previous questioner noted, mosaicism in the embryos means they can't be diagnosed properly from a single cell. Or perhaps there are other reasons why IVF fails, not related to the embryo's chromosomes.

She said more trials definitely need to be done, but at the moment there's no argument that screening embryos makes any difference. This didn't go down well in the audience, especially with Yury Verlinsky, who is director of the Reproductive Genetics Institute in Chicago, and pioneered pre-implantation genetic diagnosis. "This is a beautiful approach but you're giving the wrong answers!" he said. "Abnormality of human embryos is an obvious fact. If you remove those 70%, how can there be no benefit?"

"You must carry out your own randomised clinical trials on your own procedures to convince us that it works," countered Staessen. "So far that [evidence] doesn't exist."

June 20, 2006

Science at the solstice

To celebrate the summer, Nature is putting together a day's worth of moments in Earth’s scientific life. We’re gathering them on 21 June, the summer solstice, and publishing them next week. If you want to share moments from your day with us, feel free to do so by adding your comments here on the newsblog.

Modern lifestyles are bad for fertility

Stress, diet and exercise can dent women’s reproductive capacity.

A combination of stress, diet and exercise can dramatically affect female fertility, research on monkeys suggests. Although stress is known to reduce fertility, researchers now warn that if a woman is also dieting and exercising, the effect could be many times greater.

Read more here

Giant pandas bounce back

Population census shows raised hopes for iconic species.

The number of giant pandas in a crucial wildlife reserve in western China seems to have doubled since 1998, say researchers in China and Britain. The discovery raises hopes that this iconic species is on the road to recovery.

Read more here

Open-access journal hits rocky times

Financial analysis reveals dependence on philanthropy.

The Public Library of Science (PLoS), the flagship publisher for the open-access publishing movement, faces a looming financial crisis. An analysis of the company’s accounts, obtained by Nature, shows that the company falls far short of its stated goal of quickly breaking even. In an attempt to redress its finances, PLoS will next month hike the charge for publishing in its journals from US$1,500 per article to as much as $2,500.

Read more here

ESHRE: Protecting fertility in cancer patients

Just heard some results that could mean good news for male cancer patients. Alon Carmely from Bar-Ilan University in Ramat Gan, Israel, says he's hopeful that a drug that enhances the immune system could help protect men's testes from the effects of chemotherapy.

Chemotherapy targets cancer by killing dividing cells, so the side effects include hair loss (the drug kills the hair follicles), bone marrow depletion and infertility. Patients about to undergo treatment tend to freeze samples of sperm, but researchers would love to find a way to enable them to hang on to their fertility instead.

A drug called AS101 is already used in cancer patients as it enhances the immune system in a way that seems to make cancer cells more susceptible to treatment, and normal cells less susceptible. It has also been found to protect patients from hair loss, and bone marrow depletion. How it does this isn't really understood, but the compound, which is based on the element tellurium and apparently smells like garlic, seems to affect the immune system by several different mechanisms.

So Carmely and his colleagues decided to see whether AS101 could help protect sperm. They've tested it in mice so far. In animals injected with high doses of chemotherapeutic drugs such as Taxol, the testes were pretty much destroyed - afterwards much of the tissue had died, and the seminiferous tubules, in which sperm is produced, were empty. When the mice were given the same doses alongside AS101, there was much less damage, with plenty of sperm surviving.

Carmely now needs to check that the post-treatment sperm have healthy DNA. But assuming that's the case he's confident of being able to start clinical trials in 6-12 months. He thinks it's possible the drug could help protect fertility in female cancer patients too, but says that work will take a fair bit longer.

ESHRE: Microscopes, coffee and football

As well as the research presentations, there are also a huge number of company stalls here, mainly medical technology companies hoping to tempt fertility doctors with their latest equipment.

There's a bewildering array of microscopes, pipettes, incubators, vials and various implements whose purpose I wouldn't like to guess. Vitrolife (who provide culture media for IVF, among other things) are drawing big crowds, thanks to the fact that they have an espresso machine, and are providing the best coffee at the conference.

But top marks for ingenuity have to go to the reps from the German company MTG Medical Technology (which provides equipment for assisted reproduction and cryobiology) for managing to set up their stall's TV screen to show the World Cup. I just popped down to check how the Germany-Ecuador game was going. I was surprised to see that most delegates seemed pretty indifferent - unlike the reps, who were delighted that their team was winning 2-0.

ESHRE: The risks of IVF

A big question researchers here are asking is whether babies born after IVF are as healthy as those conceived naturally.

The bottom line seems to be that most of them look fine, though it'll be important to keep monitoring them into later life. But when it comes to understanding the biology of how culturing an embryo might affect the resulting child, there's a lot of work to do.

One of the more controversial techniques in terms of safety is ICSI (intra-cytoplasmic sperm injection), where a single sperm is injected directly into the egg. The worry is that fertilising the egg with a sperm that probably wouldn't have been able to do so naturally might affect the health of the resulting baby. The first baby born from the technique was in 1992, so there isn't a great amount of detail on how the kids turn out. Studies tracking them up the age of 5 didn't throw up major problems. Florence Belva of the Dutch-speaking Free University of Brussels has just presented to the Prague meeting the first results on ICSI kids at the age of 8. It's a small study, just 150 children, but the data are reassuring. There was no particular difference in how the pregnancies and births went, or in the results of psychological and neurological studies. The rate of "major congenital malformations" (defined as those causing functional impairment and/or needing surgical correction) went up from 3.3% in the normal children to 10% in the ICSI group. That sounds worrying, but because of the small numbers involved, the difference mostly came down to two ICSI children with a type of hernia, and five with port wine stain birthmarks. The important thing, says Belva, will be tracking the children as they go through puberty and starting wanting to have kids of their own.

Recently there's also been a number of studies suggesting that normal IVF techniques (including ICSI) could be affecting embryos by causing problems with "imprinting", a mechanism by which DNA is chemically modified in a way that affects the expression of genes. IVF children seem to have an increased risk of birth defects, and particularly of imprinting disorders, such as Angelman or Beckwith-Wiedemann syndrome, which can be caused when genes are improperly modified. Researchers are now starting to look at which genes are affected when embryos are grown outside the womb, and how the culture conditions might affect imprinting. Paolo Rinaudo of the University of California, San Francisco, speaking on behalf of his colleague Gnanaratnam Giritharan, described how the researchers cultured mouse embryos in different conditions, then used DNA chips to look at the levels of gene expression in those embryos. Thousands of genes were expressed differently in the IVF embryos, and importantly, 5 of 38 genes known to be imprinted were significantly affected, including H19, which is associated with Beckwith-Wiedemann syndrome. The nearer the culture conditions were to the conditions in the womb, the fewer genes were affected, although all the experiments showed some abnormalities. Rinaudo cautioned that mouse results don't necessarily translate into humans, but said he hopes the results will help the development of better culture conditions for clinical IVF.

At the end of the talk, one member of the audience asked whether IVF children should be given a copy of the specific conditions in which they were cultured as an embryo, presumably in case of problems in later life. Rinaudo said he wouldn't advocate that, although everyone agreed that the risks should be properly discussed with couples thinking of having IVF.

ESHRE: Gossip from the US

I had dinner last night with among others Sean Tipton, press officer for ESHRE's American rival, the American Society for Reproductive Medicine (ASRM). He's here to persuade delegates to attend the ASRM's own meeting, to be held in New Orleans in October.

The ESHRE meeting is slightly bigger than ASRM's in terms of attendance, but the Americans tip the balance (just) on the number of abstracts. Sean told me he was taken by surprise yesterday, when two Iraqi delegates asked him whether it is safe to go to New Orleans. I'm not familiar with what it's like there at the moment, but it's hard to imagine the security situation could rival that in Iraq. Sean says New Orleans is hosting its first really big conference since hurricane Katrina this week, however, and he'll be watching with interest how that goes.

He also mentioned how sperm and particularly egg donation are becoming more common in celebrity births, especially among the set of female stars having babies into their mid-40s. Some feel such celebrities could do a lot towards removing the stigma of infertility by talking about their treatment. But perhaps not surprisingly, few are willing to do so.

June 19, 2006

Brazilian outbreak raises fears over disease preparedness

Monitoring criticized after ‘unnoticed’ disease spread.

Health-monitoring experts are coming under fire for their response to a mysterious and fatal outbreak of respiratory disease in northeastern Brazil in March. News of the outbreak, which began on 10 March, only reached the international community on 4 June, when a translation of a local news article was published on the international ProMED mailing list, a service for disseminating information about outbreaks. Four posts on ProMED’s Latin American list in Portuguese had appeared the week before.

Read more here

ESHRE: Getting round Italy's law

Looking at the research that's being presented here, one of the first things to strike me is the number of papers from Italian teams trying to get round their country's restrictions on the use of in vitro fertilisation (IVF).

Italy is a strongly Catholic country of course, and in 2004 a law was passed saying that embryos cannot be frozen, that no more than three embryos can be created at once, and that no embryos can be destroyed (unless clearly already dead). Jail terms could face anyone breaking the rules. The problem is that creating more embryos than needed then picking the ones that look to have the highest chance of producing a healthy baby is a key element of IVF - how best to do that is the subject of a separate raft of papers here.

The law has clearly affected the success of IVF in Italy. Anna Pia Ferraretti of the SISMER reproductive medicine unit in Bologna, Italy, told me that in her clinic, the pregnancy rate for each IVF cycle has dropped from 35% to 24% (for 35-37 year olds at least, the drop is still present but less significant for other age groups) and the miscarriage rate has risen from 16% to 29% (in the same age group). So researchers are having to be pretty creative about improving the success rate again without falling foul of the law.

It has led to some interesting advances, that could benefit IVF more generally. Several groups are freezing any extra eggs that are collected, for example, so that if a woman doesn't become pregnant after a first cycle of IVF, she can have another round without having to donate more eggs. It's pretty routine these days to freeze semen, and embryos, but eggs are another matter -- the rate of pregnancy from eggs that have been frozen is extremely low. If you could manage it routinely though, cancer patients could freeze eggs before undergoing treatment that would damage their ovaries, or (more controversially) healthy women facing declining fertility as they age could freeze eggs for use in later life. I'll hopefully write a bit more on egg freezing in a future blog entry.

Ferraretti is working on screening eggs for chromosomal abnormalities, so that the best eggs can be selected before they're even fertilised. You can't check the chromosomes of the egg itself without destroying it so in Ferraretti's study, the chromosomes of the "polar body" were screened instead. The polar body is a structure formed as an immature egg divides in two. One half goes on to become the mature egg, the other half -- the polar body -- has the same chromosomes but simply degenerates. The egg has to be inseminated within 6 hours of this division, so for Ferraretti and her colleagues it was a race to complete the chromosome analysis in time. The screen didn't improve the number of women getting pregnant, but the subsequent miscarriage rate was reduced to 14%, roughly what it was before the restrictions were brought in.

Ferraretti is delighted with the result, and hopes that as techniques for analysing the chromosomes in the polar body get better, it may be possible to improve the pregnancy rate as well. And although she admits that such results will be beneficial for fertility treatment, she's keen to avoid any suggestion that the Italian restrictions have been good news. "I am afraid people will look at the results and think the law is OK," she told me. "But it's not at all!" It's the patients that lose out, she says, as they are forced into using experimental techniques (unless they go abroad for treatment).

There could be another downside too -- loss of the expertise that IVF patients in Italy are so reliant on. Ferraretti says she has considered leaving Italy to work somewhere the laws are less restrictive. "I'm so depressed to have such limitations," she says. "I would like to be more free to adapt the best technique to each couple. I have the experience, I have the skills, and I would like to be able to do that." By putting together the latest techniques she believes it is possible to minimise the number of embryos used, "with respect for the patient and the embryo".

ESHRE: All about stem cells

Hello! I'm Jo Marchant, Nature's news editor, and I'm here in Prague for the 22nd annual meeting of ESHRE, the European Society of Human Reproduction and Embryology. It's a huge and wide-ranging meeting -- I'm told there are over 6000 delegates here, including infertility specialists, embryologists, geneticists, stem cell scientists and developmental biologists.

Today is the first day of the meeting proper, but I'll post about that in a bit. First, an update on the latest in stem-cell research. Yesterday I attended a pre-congress course on stem-cell derivation and therapy organised by Anna Veiga of the Center of Regenerative Medicine in Barcelona, and Luca Gianaroli of the Sismer Reproductive Medicine Unit in Bologna. I was there to grab audio interviews with as many of the speakers as possible, asking them about the state of stem-cell research and its future potential for a special podcast on stem cells that Nature is putting together. The podcast is to run alongside a stem cell supplement that's going in the 29 June issue of Nature. That podcast will also include a studio debate and interviews with some of the authors of the Nature articles, and it'll be available here from late on 28 June. My stuff will be edited down into a short package for that podcast, and in the meantime you can listen to a fuller version of some of the interviews I did here .

The first interview is with Alan Trounson of Monash University in Melbourne. He was a pioneer of IVF technology, and is now a leading stem-cell researcher. He told me how excited he is about his own work using stem cells to treat respiratory disease, and about how he believes that adult stem cell therapies will help pave the way for treatments using embryonic stem cells.

The second interview is with Stephen Minger, of King's College London. He is one of a select handful of researchers who have a licence to derive embryonic stem cell lines in the UK. He's using embryos rejected from IVF treatment after pre-implantation genetic diagnosis (PGD). He said he'd like to try somatic cell nuclear transfer (or therapeutic cloning, where stem-cell lines are derived from a cloned human embryo, with the ultimate aim of creating lines that are matched to a patient's own cells). But he favours the idea of starting off by using non-human eggs for the cloning, until the efficiency is high enough to justify using donated human eggs.

Finally I spoke to course organiser Luca Gianaroli. He told me how he believes one of the most exciting things about stem-cell research at the moment is what it's telling researchers about basic embryo physiology -- which is crucial for infertile couples of course, as well as those carrying certain genetic diseases.