Column – Science Media Centre
SMC Heads-Up: GM risk assessment, smoking genes and bird extinction
Issue 224 29 March – 4 April 2013
How safe is ‘safe enough’?
A group of academics claim GM products such as soybeans are not being subjected to sufficient scrutiny from regulators. But regulators counter that there is no evidence of extra risk to justify it.
A recent analysis by Professor Jack Heinemann, director of the University of Canterbury’s Centre for Integrated Research in Biosafety, and colleagues, critically examined several regulatory bodies and how they assess genetically modified organisms carrying a modification that produces a molecule that can inhibit other genes (double stranded RNA; dsRNA).
The study, published last week in the journal Environmental International, concluded that, “regulatory bodies are not adequately assessing the risks of dsRNA-producing GM products.”
The authors put forward their vision for an ideal formal assessment procedure, involving multiple levels of bioinformatic, in vitro, animal and possibly human clinical assessments before approval could be granted in each individual case.
Prof Peter Langridge, an Australian plant geneticist, dismissed the criticism in comments provided to the SMC, stating, “in their article, this group proposes regulatory procedures that are clearly designed to block the technology, not address safety issues.”
“The regulatory agencies are not only fully aware of the technology [in question] but they are actively seeking scientific input into the safety assessment. We are fortunate in Australia and New Zealand to have very effective and profession regulatory procedures that have ensured we now enjoy the safest food in our history.”
Food biotechnology senior lecturer at the University of Melbourne, Dr David Tribe, added, “the double-stranded RNAs that are discussed in [the paper] are in every bit of food we eat, and in perhaps every plant and animal on the planet, and have been for millennia.”
He went on to emphasise that much less is known about conventional plant varieties that come to market without regulatory oversight, in contrast to new crops developed with GM techniques.
Chief Scientist Paul Brent of Food Standards Australia New Zealand, the agency responsible for approving genetically modified products for use in both countries, appeared today alongside Prof Jack Heinemann on Radio New Zealand’s Nine to Noon programme to address the issue.
You can read comments in full and further media coverage of the issue on the Science Media Centre website.
Smoking genes predict risk
Your DNA may play a significant role in determining whether or not you end up a smoker – and how easy you find it to kick the habit.
Many large studies have identified particular gene variants that are more common in smokers than other people, suggesting the they play a role in nicotine dependence.
Now an international team of researchers have used these genetic clues develop a ‘genetic risk profile’, and to see how accurate it is, they have road-tested it on the on a well known sample of Kiwis: the Dunedin Birth Cohort.
Researchers analysed data from the long-term study of 1,000 New Zealanders to identify whether individuals at high genetic risk got hooked on cigarettes more quickly as teens and whether, as adults, they had a harder time quitting.
The results, published today in JAMA Psychiatry, showed that a person’s genetic risk profile did not predict whether he or she would try cigarettes. But for those who did try cigarettes, having a high-risk genetic profile predicted increased likelihood of heavy smoking and nicotine dependence.
This link was most apparent for teenagers; Among teens who tried cigarettes, those with a high-risk genetic profile were 24 percent more likely to become daily smokers by age 15 and 43 percent more likely to become pack-a-day smokers by age 18.
As adults, those with high-risk genetic profiles were 22 percent more likely to fail in their attempts at quitting.
“The effects of genetic risk seem to be limited to people who start smoking as teens,” said author Daniel Belsky, a post-doctoral research fellow at Duke University.
“This suggests there may be something special about nicotine exposure in the adolescent brain, with respect to these genetic variants.”
The authors noted that their genetic risk profile isn’t yet accurate enough to be used to identify high-risk teens reliably, but it does highlight the critical adolescent period in addiction development.
“Public health policies that make it harder for teens to become regular smokers should continue to be a focus in antismoking efforts,” Belsky said.
You can read international news coverage of the study on the Science Media Centre website.
On the science radar…
Pacific bird loss extensive
Over-hunting and deforestation by Pre-European settlers in the Pacific led to extensive loss of bird life, according to a new study.
While human migration into the Pacific region was known to have caused the extinction of many bird species, exact numbers have been sketchy.
Now, in a new study published this week in PNAS, scientists used fossil records from 41 Pacific islands to model the number of birds lost over the last 4,000 years.
Their findings show the extinction toll may have been as high as 1300 bird species – about 10% of the current bird species in the world, say the researchers.
Author Prof Richard Duncan, from the University of Canberra (previously at Lincoln University, NZ), told Science magazine that while hunting would have lead to many of the extinctions, burning of forests would also have played a major role.
“You can imagine, when you don’t have chainsaws and things, the easiest way to clear forest is to set it on fire,” he said.
The authors note that New Zealand got off lightly as it is a large, mountainous and wet island, suffered less deforestation, and had more places for birds to hide from hunters.
You can read a round up of international media coverage on the Science Media Centre website.
Quoted: The Vote, TV3
“If you are still eating poorly after this change then you are offsetting the health costs that you will be generating in the future when the diabetes zombie apocalypse hits, okay?”
GM Regulation: Experts comment on a new paper calling for tighter risk assessments of a particular genetic modification.
In the news:
Pacific bird loss: Human settlement of the Pacific resulted in an immense loss of native bird species. Read coverage of new research.
Flu warning: Experts are encouraging New Zealanders to get their flu jab as a potentially nasty flu season looms.
Some of the highlights from this week’s posts:
Chocolate! and just in time for Easter – Does chocolate lower your stroke risk? Alison Campbell casts a critical eye over the reported benefits of the sweet stuff.
Using the ‘bigfoot genome’ for 21st century biology – Aimee Whitcroft highlights a neat new ‘citizen science’ class on unlocking the secrets of genomes – real or not-so-real.
Visualising plastic pollution in the world’s oceans – Guest Blogger Timo Franz (from data, design and development outfit Dumpark) highlights a new visualisation of the ‘great Pacific garbage patch’.
Please note: hyperlinks point, where possible, to the relevant abstract or paper.
Predator-free fish streams: Trout threaten the survival of NZ native fish, both by direct predation and competition for resources. A new study confirms the negative impact of introduced brown and rainbow trout species on native galaxiid fish. The authors suggest taking advantage of galaxiids’ unique climbing abilities – the fish can crawl upwards along steep rock chutes – to create barriers that are impassable to trout.
Science for Conservation
‘Smoking genes’ predict risk: New Zealand researchers, in collaboration with US and UK colleagues, have developed a ‘genetic risk score’ and road-tested it on the Dunedin Birth Cohort to see if it can predict who initiates smoking and to what extent. The authors noted the effects of genetic risk seem to be limited to people who start smoking as teens. For instance, among teens who tried cigarettes, those with a high-risk genetic profile were 43 percent more likely to become pack-a-day smokers by age 18.
Obesity breathalyser: The content of a person’s breath may indicate how susceptible they are to weight gain, according to a recent study. People whose breath has high concentrations of both hydrogen and methane gases are more likely to have a higher body mass index and percentage of body fat, according to the findings. The combination of the two gases signals the presence of a microorganism that may contribute to obesity, say the authors.
Electrifying waggle dance: New research suggests that there is more to the honeybee’s waggle dance than meets the eye. During the dance, which directs fellow bees to sources of nectar, the dancing bee emits static and modulated electric fields which, according to the new research, bees can detect and be trained to respond to. The authors conclude that these electric fields are an important and overlooked component in honey bee dance communication.
Proceedings of the Royal Society B
Some of the policy highlights from this week:
R&D spending up: Statistics New Zealand data released today that shows businesses in New Zealand spent $1.2 billion on research and development in 2012 – an increase of almost 25 per cent since 2010.
Upcoming sci-tech events
• Mad on radium: New Zealand in the atomic age – Cafe Scientifique with Rebecca Priestley – 28 March, lower Hutt.
• Human evolution – we are family – A chalkle meetup with Michael Harvey – 2 April , Wellington.
• Cryptogenomics – using the “bigfoot genome” for 21st century biology – A chalkle meetup with David Winter – 2 April , Wellington.
• What is the value of science in NZ? – NZAS conference – 3 April, Wellington.
• Open data – letting it loose on the crowd – BIG DATA discussion panel with Kim Hill – 3 April, Wellington.
• What if… What you eat controlled your children’s genes? – “What if Wednesday” lecture from Prof Ian Shaw – 3 April, Christchurch.
• The Ecological View of Cats – Public talk from John Flux – 4 April, Wellington.
For these and more upcoming events, and more details about them, visit the SMC’s Events Calendar.