GMO Food for Thought

Completed genome

The ability to improve health and disease management of cattle received a major boost with the release last week of the most complete sequence of the cow genome ever assembled.

Developed by an international consortium including the CSIRO, the new bovine sequence contains 2.9 billion DNA base pairs and incorporates one-third more data than earlier versions.

CSIRO's Dr Brian Dalrymple said, "We can use this data to identify those genes that are involved in important functions like lactation, reproduction, growth rate and disease resistance.

"This is just the beginning of a revolution in the way we produce our animals and food."

Beefing it up

Commercial tests are now available to identify tenderness and marbling in beef, using laboratory analysis of an animal's DNA, which can be extracted from tail hair roots.

The tests were developed by a consortium comprising the Cattle and Beef Quality Cooperative Research Centre, CSIRO Livestock Industries and Meat and Livestock Australia.

The project identified a particular gene form associated with either beef tenderness or toughness.

This means breeders can improve tenderness by removing animals with two copies of the tough gene and also by selecting to increase the frequency of the tender gene.

According to the CSIRO, gene mapping is low-risk research and is conducted in minimum-security laboratories.

Australia's first cloned and genetically modified calves were born in 2002. They contained an extra gene for milk protein production, which could increase it by 10 per cent.

Unfortunately, due to difficulties in the early stages of development, only one of the four calves survived.

Genetic modification is different from selective breeding. So is it tampering with nature?

What is genetically modified food?

It is food produced from any crop or animal that has been genetically altered during its production, with modifications usually involving changing one of the 30,000 to 50,000 genes making up an organism.

The debate on GM food and its implications for human health continues to rage.

Those in favour would say:

All GM food reaching us has been assessed to meet safety regulations.

Because of gene technology we can have tastier, healthier, nutritionally improved food at a cheaper price because genetic modification helps farmers reduce wastage.

Many GM crops are not substantially changed so there is no need to separate them from unmodified crops. Those against would say:

We don't have conclusive proof GM food is safe.

The technique is imprecise and the science too new to guarantee we won't have problems in the future.

There are already traditional plant and animal breeding techniques that can improve our food.

We can't always choose whether we eat GM food as the current labelling doesn't tell us.

The impact on the environment

Supporters say all GM crops must be carefully assessed for their impact on the environment before they are planted, and that better use can be made of agricultural land as GM crops can grow in conditions unfavourable to traditional crops.

However, opposers say genetic pollution could happen, with unwanted consequences. If this happens, they say, agriculture and the environment will be irreversibly altered.

At the conference, Greenpeace GE campaigner Louise Sales, said despite approval by regulators in many countries, serious concerns remained, including biodiversity impacts, genetic pollution, increased pesticide use and the emergence of pesticide-resistant weeds and insect pests.

"There has been no assessment in Australia of the impacts on native wildlife, beneficial insects, native plants or the ecology of Australia's agricultural areas," she said.

In Australia, cotton and carnations are the only two genetically modified commodities available commercially. The Federal Government has approved canola for commercial release but because of State Government moratoriums it is only being sown in small field trials.

It is estimated at least 70 per cent of processed foods on shelves in the US contain ingredients and oils from biotech crops. The first biotech crop, a tomato, was sold in 1994; the first commodity crop, an insect resistant corn, was sold in 1996. The majority of large commercial farms plant genetically modified crops and there is no effort to distinguish those from non-biotech crops and foods.

In the EU, the issue of whether it is possible to keep GM and conventional crops completely separate is causing much discontent, with 11 GM seeds approved or small commercial plots, while a number of other EU countries have banned GM organisms.