Designer life: inside the GM labs

GM research can now go ahead - but what exactly is it? ANDREW LAXON reports on what our scientists are up to.

Salmon with lumpy heads. Cows with human genes. Flowers that change colour and vegetables that fight diseases by themselves.

As the genetic modification debate has raged over the past few months, most of us have formed a sketchy picture of what GM research actually involves.

But now that the Government has made its decision - no commercial releases for two years, field trials under strict conditions and an all-clear for work in contained environments such as laboratories - what will it mean?

GM research can be divided into three main fields: animals, plants and medicines.

Genetically modified food, which concerns many consumers, is not commercially produced here, although processed food with GM ingredients will have to be labelled by December next year.

This is an overview of some of the main experiments under way or recently carried out in New Zealand. Virtually all will be able to continue in theory, although some may now struggle financially because of increased costs of field trial security.

Animals

Cattle: Possibly the most famous genetic experiment in this country is the insertion of a human gene into cattle.

Scientists at AgResearch in Ruakura added cattle milk casein genes and disrupted an existing protein gene to vary the proteins in cow's milk. But they also added a human protein called myelin into the genes of three cows.

The aim is to reproduce the protein in the cows' milk. It can then be purified and ultimately tested for its potential to treat multiple sclerosis.

Sheep: Many scientists try to identify the best genes through GM techniques and then improve animals by natural breeding.

For instance, Lincoln University has identified variants of a gene involved with increased lamb growth. Sheep with favourable variants are selected for further breeding using traditional methods.

Scientists at AgResearch and elsewhere are working on ways to knock out a protein called myostatin, which is believed to restrict muscle growth and development. They have found the gene is inactive in double-muscled Belgian Blue cattle and are trying to replicate this in sheep.

Lincoln University has been breeding transgenic sheep with a gene from mice designed to increase wool growth.

A DNA mixture of the mouse promoter gene and the sheep's growth factor gene was injected into sheep embryos, which were then delivered naturally by ewes. The male offspring then mated with ordinary ewes and the transgenic sheep they produced has been monitored for signs of increased wool.

Lincoln researchers have also worked out the amino acid sequence of a protein which makes lamb tender. They believe lamb becomes tough when the gene involved is not active enough.

Another project involves a flock of transgenic milking sheep producing milk with human Alpha 1 Antitrypsin (hAAT), a protein used to combat cystic fibrosis.

Salmon: The most controversial GM experiment here to date became a warning of what can go wrong.

NZ King Salmon put a growth hormone in the fish, which grew three times faster than normal. Some developed lumps on their heads. When news of the "Frankenfish" experiment became public, the company stopped the trials and killed and buried all the transgenic salmon. There are no plans to resurrect the programme.

Possum control: Landcare Research scientists plan to feed GM carrots and potatoes to female possums to make them sterile. The project could take five to 10 years to progress to field trials.

Other scientists have questioned whether the possums could develop biological resistance, a criticism aimed at many other GM projects.

AgResearch scientists at Ruakura have also been investigating ways to block antibodies in possum breastmilk which protect their young against diseases.

Wasp control: Researchers plan to insert a toxic gene into bacteria found in the gut of wasps, killing the insects in their nests. The gene is not yet identified but a possible bacterium has been isolated.

Stoats: In a similar project, Massey University is investigating gut bacteria for biocontrol of stoats.

Plants

Potatoes: Scientists at Crop and Food Research in Christchurch have developed genetically modified Red Rascal potatoes which they hope will be resistant to the tuber moth pest. The aim is that a gene in the plant will produce an insecticide in the leaves. If it works, potato growers would not need to use herbicide to control the moth.

Peas: The same scientists have given peas a genetic implant of the alfalfa mosaic virus, which they hope will give the peas immunity against the disease itself.

GM research is also under way on many other vegetables: onions (for better performance), lentils (herbicide resistance), asparagus (herbicide resistance, longer shelf life), sugarbeet (herbicide resistance), and brassicas, such as broccoli, cauliflower and cabbage (resistance to viruses, club root, aphids and herbicides, longer shelf life).

Apples and kiwifruit: Research focuses on finding out what genes in these fruit do. HortResearch maps genetic patterns, stores genetic codes in bacteria to form "gene libraries" and makes transgenic plants which over- or under-express genes so researchers can assess how they function.

Researchers also fast-breed fruit in the laboratory to identify plants with the best genes, which are then bred and crossbred traditionally. HortResearch aims to extend this to breed trees and shrubs which can break down toxic residues in soil.

Tamarillos: HortResearch has immunised these against tamarillo mosaic virus.

In the longer term, HortResearch is identifying genes responsible for the flavour and healthy properties of fruit. It is isolating them so they can be manipulated in fruit species in future, although any move to do this could run into consumer resistance.

Flowers: Crop and Food Research scientists have developed a technique to change the colour of flowers and other plant foliage, by altering the biochemical pathways of flavanoids and carotenoids.

Pine trees: Forest Research in Rotorua is trying to create pine trees with less lignin, which enables the trees to stand up straight but is expensive to remove during pulp and paper production. To achieve this, researchers fire microscopic DNA-coated gold bullets into radiata pine tissue.

Forestry is a crucial area for research, as it accounts for 11 per cent of exports.

White clover: This important pasture plant has no known natural genetic resistance to common pests such as grass grub and porina moth.

AgResearch has implanted genes with insect-killing proteins from other plants and animals into the clover. It is also looking at boosting energy in white clover and ryegrass by introducing genes which control carbohydrate levels.

Medicines

This is an important but relatively uncontroversial area, as most anti-GM groups, such as Greenpeace, do not object to experiments inside the laboratory.

GM techniques are used around the world for medical research, especially developing new drugs.

There are GM-derived drugs and vaccines already available in New Zealand for conditions, including diabetes, haemophilia, cystic fibrosis, breast cancer, infertility and Gaucher disease.

Many research trials use genetically modified mice, which have genes inserted, mutated or deleted to mimic human diseases.

One of the most common techniques, used extensively in cancer research, but also for asthma and multiple sclerosis, is to knock out immune system genes in mice.

Otago University researchers use transgenic mice which have human genes involved with the assembly of lipoproteins - fatty particles associated with susceptibility to heart disease. Other scientists at Otago have discovered an antibacterial protein which fights streptococcal infection, commonly known as sore throat.

The Government's decision could also clear the way for a new cholera vaccine, which has been held up for two years, despite clearance from the Ministry of Health, because it would have introduced a live genetically modified organism.

Tuesday's decision creates an exception for "direct benefits to human health or animal health" but the vaccine will still need formal approval from the Environmental Risk Management Authority.

nzherald.co.nz/ge

Report of the Royal Commission on Genetic Modification

GE lessons from Britain

GE links

GE glossary