Secluded isles face unknown GE risk

On the eve of the lifting of the GE moratorium, science reporter SIMON COLLINS finds the jury still out on safety.

In a remote corner of the Earth's largest ocean, two large islands and a few offshore islets lie uniquely vulnerable to biological intrusion.

Here, isolated from major land masses for the past 130 million years, distinctive plants and animals have evolved - not just birds such as moa and kiwi, but a whole range of life forms. Ninety per cent of the islands' insect species are not found anywhere else.

Until a very recent species, homo sapiens, finally colonised these islands only 700 years ago, there were no land mammals to threaten the birds and insects that lived here.

"This has led to an extreme susceptibility to impacts from introduced organisms," says a Landcare Research study, Environmental Risks to the New Zealand Flora from Transgenic Crops.

In a shorter time than anywhere else on the planet, human beings have brought more than 20,000 plant species into this country. Today, there are more introduced species growing in the wild than native plants. Hybridisation, or crossing between different species through natural transfer of genes via pollen or bacteria, is happening here at a far faster rate than in longer-settled countries.

On Wednesday, when New Zealand lifts a two-year ban on releasing genetically modified (GM) organisms into the environment, our plants and animals will be opened in principle to a new form of interference - deliberate transfer by humans of genes designed to achieve precise results, such as faster growth or disease resistance.

Taxpayers are now spending $120 million a year on biotechnology research, including $20 million on developing genetically modified organisms. On top of that, the Ministry of Research, Science and Technology is spending $6.6 million this year on studying the potential effects of GM on our environment, economy and cultures - more than double its budget for organic agriculture.

But half of the research on the potential effects of GM is being done by the crown research institutes which are doing most work on actually producing GM products: AgResearch, Crop and Food Research, HortResearch and Forest Research.

Ruakura-based AgResearch has already genetically modified cows to produce milk with higher levels of certain proteins. It has state funding of $5.4 million a year for the next five to seven years to use cows as "factories" making ingredients for medicines for diseases such as multiple sclerosis.

Crop and Food, based at Lincoln near Christchurch, has genetically modified peas, potatoes, onions and some brassicas, such as broccoli and cauliflower, to resist diseases such as the potato tuber moth. Similar to AgResearch but this time with plants, it also wants to develop natural medicine "factories".

HortResearch, based at Auckland's Mt Albert Research Centre, has grown GM tamarillos and created the world's biggest database of fruit gene sequences. It is using genetic analysis to breed new plants conventionally, such as an apple with a disease-resistance gene.

Rotorua's Forest Research has genetically modified pine trees to withstand weedkillers, allowing it to spray weeds without damaging the trees. Now it is trying to create trees with less lignin, a substance which makes wood hard but has to be taken out to make paper.

These same institutes have state funding to assess the environmental impacts of GM, in cooperation with Landcare and the Institute of Environmental Science and Research (ESR), which are not developing any GM products themselves.

"We have a sort of community now of people who are working in impacts research, because a lot of us are based in crown research institutes that are also developing the technology," says AgResearch's Travis Glare, who co-convenes the group with Crop and Food's Tony Conner.

"We have to make sure that we are both working properly and seen to be independent."

In many countries, a huge effort is going into checking the effects of GM. A three-year study of GM crops on 60 British farms found last week that there were more bees and butterflies around maize genetically modified to withstand weedkiller than around unmodified crops.

But the opposite was true for sugar beet and oilseed rape (canola), with conventional crops having more weeds around them, and therefore more bees and butterflies.

In New Zealand, a team of Landcare scientists led by Bill Lee in Dunedin is building up a database of all of New Zealand's native and introduced plants, recording how often they cross naturally with other species. The team has identified 14 introduced plants, including potatoes, tomatoes and carrots, which are similar enough to some native species to cross easily with them by pollen or seed. It is now looking at what kind of separation distances should be imposed to make sure GM crops do not cross with non-GM relatives.

For many years, the seed certification industry has imposed isolation distances ranging from about 100m to 3km, depending on how pure farmers want a new seed crop to be. Lee says these distances will need to be longer for plants where pollination is involved.

Crop and Food researcher David Teulon says honeybees "regularly forage [for pollen] 5km from hives but they will go much farther if they have to".

In a glasshouse at Mt Albert, HortResearch scientist Louise Malone is studying whether bees die sooner if fed on plants that have been genetically modified to repel pests, for example by incorporating genes from Bacillus thuringiensis (Bt) which kills many bugs.

Perhaps surprisingly, since Bt is designed to kill, she has found it does not kill bees. She believes the reason is that Bt bacteria are common in the soil everywhere, so bees and most other creatures are already immune to them.

"That's why Bt is used in organic orchards."

Her colleague Libby Burgess has fed GM plants to leaf caterpillars and watched to see whether there was an effect on either the caterpillars or a native beetle, which eats them.

She found no effect on the feeding, growth, survival or reproduction of either species. She is still watching in case an effect turns up in the next generation.

In Rotorua, Forest Research scientist Christian Walter has been sneaking out for the past few months to a "confidential site" where he planted 52 genetically modified pine trees and 16 GM spruces early this year. He is checking for another possible environmental effect - "horizontal gene transfer", or the transfer of genetic elements out of the trees directly into soil bacteria.

This kind of transfer is widespread between bacteria - tiny, single-cell organisms which can swap genes through the bacterial equivalent of sex, called "conjugation". But so far Walter has not found a single case of gene transfer between the trees and bacteria.

Clive Ronson, professor of genetics at Otago University, is not surprised. "There are isolated examples of that sort of transfer, but they are extremely rare and quite hard to prove," he says.

"There has been ample opportunity for evolution to select whatever genetic combinations are fit. So the concept that a transfer from a GM plant to a bacterium will have an evolutionary consequence [i.e. be passed on to other bacteria] doesn't seem very likely."

However, Jack Heinemann, an impish American who is director of the Institute of Gene Ecology at Canterbury University, believes the state-funded researchers are simply looking in the wrong places. "There are up to two billion bacteria per gram of soil. The numbers are immense," he says.

If only one in 100 million bacteria pick up a genetic element from a plant, you would need to examine the genetic structures of many hundreds of millions of bacteria to find it. "No one is capable of that."

Instead of searching for such an extremely rare event, he says, look at the evidence that it has occurred in the recent past. Take antibiotic resistance. In less than 50 years there have been changes in four separate proteins in the pneumonia bug streptococcus pneumonia which first made one of the bugs resistant to penicillin and then passed the immunity to a quarter of all streptococcus pneumonia bugs in the world.

"When a streptococcus dies, some of its DNA can leak out and a neighbouring one can take up that DNA," Heinemann says. He concludes that we should research the potential dangers of GM to human health before rushing in to try to make money out of the technology.

Conner is unfazed by the criticism. Health risks, he says, cannot be assessed in any general way and should be scrutinised case by case.

The Foundation for Research, Science and Technology, which allocates most of the Government's research spending, says the emphasis on researching environmental vulnerability rather than health impacts was recommended by the royal commission.

"We haven't excluded health, but it hasn't been a priority for us, and we haven't got anything significant in that area," says its portfolio planning manager, John Smart. "We have invested in these programmes for some time. When we come to review them in about two years, we may at that point look to broaden the scope."

Despite all the research to date, opinion polls show that the public has yet to be convinced of the value of GM products, either on these remote islands or on the continents where we sell our wares.

October 29 therefore looks set to mark merely a new phase in the debate. While the research continues, New Zealand's future - GM or otherwise - still hangs in the balance.