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Date:

November 18, 2001

Subject:

Edible vaccines, Ehrlich, Golden Rice, Food Security

 

- Today's Topics in 'AgBioView' -

* Making vegies even healthier - Vaccine in food may save millions
* Seeds of Health
* Easing fears cited as key to future of biotech crops
* Ehrlich Blasts Optimism
* GOLDEN RICE: PROOF OF CONCEPT AND BEYOND
* Biotech crucial for food security
* ... and is safe for humans, says
* 'Gene Gun' Blazes Away in Biotech Fight on Famine

Making vegies even healthier - Vaccine in food may save millions

The Sunday Telegraph(Sydney)
By GRAHAM PHILLIPS
November 18, 2001

THERE'S a natural food to which millions of people are allergic. So allergic, in fact, that some have died from eating it -- yet there's no outrage.

This food is even sold in health-food shops: it's called peanuts. The only reason there's no outrage is that nuts are one of Mother Nature's creations, not the work of genetic engineers. The arguments over genetically modified foods have an air of absurdity about them. Although every product scientists develop must undergo a battery of tests -- and rightly so -- most natural products get away completely unchecked.

When evaluating genetically engineered foods, the aim should not be to guarantee that they're perfectly safe, because there's no such thing.

Instead, altered corn and soy beans should be shown to be no more dangerous than their natural counterparts. And so far, it seems that's generally the case.

But the next battle in the debate will be more interesting. Scientists are now planning something more than extra-tasty tomatoes and pest-resistant crops. They're putting drugs into fruits and vegetables.

One idea is to put a vaccine for hepatitis B in lettuce. It would be a matter of engineering the plant so its genetic machinery manufactured a part of the hep B virus, which would become available in the leaves. People could be immunised by simply eating some of this lettuce.

It would work the same way as a traditional vaccine. The immune system would react to the virus part and build up defences to it.

When the real, complete virus came along, the same defences would be able to kill it off.

There's no doubt munching on lettuce would be more pleasant than getting a shot. But drugs in fruit and veg?

There'd be no need for a safety check, because no-one would deny that, compared to the normal variety, GM lettuce would have a huge effect on human bodies.

People would normally need a prescription before being allowed to swallow the chemicals in it.

Of course, measures to ensure medicinal foods are never mixed up with regular ones would need to be developed.

And we'd need watertight assurances there would be no cross-pollination between GM and regular varieties.

Given the outcry over the genetically modified foods produced so far, these more dangerous ones are going to be a much greater battle for scientists.

Yet it may be a battle worth fighting, because of the potentially huge benefits from putting medicines in foods.

Much of the world's population is unvaccinated against common diseases, and millions of adults and children are dying every year as a result.

Disease doesn't recognise national borders, and new, drug-resistant varieties are appearing. We are all at risk because of this pool of unimmunised people.

If vaccines were put in fruit and vegetables, Third World countries could grow their own and cheaply inoculate their populations. We might even rid the world of many more diseases, as we did with smallpox.

It would be good if it was possible to leave the Frankenfood scaremongering behind this time around, and think through the costs versus the benefits in a more rational way.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++

http://www.ifpri.org/

Seeds of Health

A Newsletter for Practitioners in Agriculture and Human Nutrition
Seeds of Health is published three times a year, presenting recent scientific findings and issues relevant to agricultural strategies, and in particular plant breeding, for improving micronutrient nutrition in developing countries.
+++++++++++++++++++++++++++++++++++++++++

Easing fears cited as key to future of biotech crops

Kansas City Star
November 17, 2001
By BILL GRAHAM

Genetically engineered foods will gain acceptance with consumers
only if they are properly regulated and if the public has a clear
understanding of their benefits, experts said Friday at a National
Association of Farm Broadcasters conference in Kansas City.

"We believe the engineered crops, if used properly, can greatly
benefit consumers, farmers and the environment," said Michael F.
Jacobson, director for the Center for Science in the Public Interest.
"But if misused, they can cause great harm."

Crops with artificially altered genes are increasing yields while
lowering the use of chemicals such as pesticides, said Jacobson,
co-founder of the advocacy group for healthful food, based in
Washington, D.C.

Some engineered crops, such as Bt corn planted in Missouri and
Kansas, are developed to produce a toxin in plant tissue that kills
specific yield-reducing insects, such as corn borer worms. But some consumers fear tinkering with natural processes will
harm food safety, Jacobson said to several hundred people in
attendance at the Westin Crown Center hotel.

"It behooves the industry of biotechnology to address and value
those concerns," he said, "and for them to adhere to structures and
rules to ensure the food is safe."

The industry must be clearly regulated, and the reasons for
decisions, based on science, must be clearly explained and open to
the public to build trust, Jacobson said.

There are concerns that genetically modified crops will pass
traits to wild but related plants and create ecological problems, he
said. There also are concerns that proteins will be created that are
harmful to humans.

Thorough testing can solve those questions, but rules must be
followed. Farmers are currently required to plant normal crops along
with Bt crops to prevent insect pests from building resistance to the
new Bt crops. One study showed that there was poor enforcement and
that some farmers were not following those rules, Jacobson said.

Congress should pass a law with better approval and enforcement
processes, he said. In addition, that law should include financial
aid to help universities and small research companies meet testing
requirements so research is not limited to large corporations. Also,
more research support is needed to broaden the scope of plant
genetics research beyond the most commonly planted grains, Jacobson
said.

But the potential benefits from bioengineering are being
overshadowed in public opinion by unscientific fear, said ecologist
Patrick Moore, a founder of the Greenpeace environmental group and
one of its key leaders for 15 years. Moore now works for sustainable
forestry in British Columbia but is at odds with Greenpeace, in part
because he believes genetic engineering can provide environmental
benefits.

Moore noted that extensive research has found no human health
problems from biotech foods. Instead, they have been proved to
improve nutrition and the environment. Yet some environmental groups
battling genetic engineering have frightened the public about eating
fruit and vegetables.

"I believe the campaign of fear now waged against genetic
modification is based on fantasy and a complete lack of respect for
science, logic and knowledge," he said.

America faces far greater food threats from bioterrorism,
nutrition deficiencies, obesity and allergies, said Bruce Chassey,
biotechnology dean at the University of Illinois.

Bringing a genetically engineered product to market takes up to
10 years, and the product must pass through nine federal regulatory
steps, Chassey said. So issues are being addressed. But new
components may be needed to increase consumer confidence in crops
that can improve health and environment worldwide.

"Is it moral not to use a technology that can save lives?" he
said.
+++++++++++++++++++++++++++++++++

Date: 17 Nov 2001 13:15:39 -0000
To: AgBioWorld-feedback-1256@lb.bcentral.com
From: "Ferdinand Engelbeen"
Subject: Ehrlich Blasts Optimism

I recently have read large parts of the book of Lomborg. While I don't
agree on several points, and have some additions, he is remarkably
right to-the-point about a lot of scares, including GMO's, pollution and
global warming (where he is too polite, in my opinion).

In contrast, many predictions of Paul Ehrlich have been proven false.
In a bet (for a one-month wage) with the late Julian Simon, he might choose
10 industrial raw materials or products for which he predicted that they
should be exhausted or far higher in price after 10 years. Julian Simon
predicted for all ten that they would be cheaper, compared with the
initial price in constant dollars. Simon did win the bet for all ten...

Thus don't bother about Ehrlig, he is one of the big promotors of the
"litany", claiming that our environment is going worse and worse, while
all facts show the opposit...

Sincerely,

Ferdinand Engelbeen
+++++++++++++++++++++++++++++++++++++++++++++

GOLDEN RICE: PROOF OF CONCEPT AND BEYOND

Seeds of Health
October 2001

Rice is the major staple food for hundreds of millions of people.
It is generally consumed in its milled form with outer layers
removed. The main reason for milling is to remove the oil-rich
aleurone layer, which turns rancid upon storage, especially in
tropical and subtropical areas. As a result, the edible part of rice
grains consists of the endosperm, filled with starch granules and
protein bodies, but it lacks several essential nutrients for the
maintenance of health, such as carotenoids exhibiting provitamin
A activity. Thus, reliance on rice as a primary food staple contributes
to vitamin A deficiency, a serious public health problem
in at least 26 countries including highly populated areas of Asia,
Africa and Latin America.

A complementary intervention to existing strategies for reducing
vitamin A deficiencies in the highest-risk countries is to fortify
the major staple food, rice, with provitamin A through plant
breeding. This can only be achieved by recombinant technologies
rather than conventional breeding, due to the lack of any rice
cultivars producing this provitamin in the endosperm. Both
because the transformation of rice is well established and
because the entire carotenoid biosynthetic pathway has been
molecularly identified recently, it appeared feasible to introduce
the complete provitamin A (ß-carotene) biosynthetic pathway
into rice endosperm by genetic engineering.

RECENT RESEARCH AND NEW LINES

As reported earlier, three genes were added simultaneously to
rice: psy and lyc (both cloned from Narcissus pseudonarcissus,
and cryt1 (cloned from Erwinia uredovora). The measured level
of β-carotene in one gram of the transformed rice, commonly
referred to as "Golden Rice," was 1.6 µg.

More recently we have been investigating an unexpected
carotenoid pattern in the transgenic rice seeds. Currently it cannot
be ruled out that the transformation using the bacterial crtIgene
promotes a hitherto unknown feedback mechanism enabling the transcriptional activation of carotenogenic genes.
To test this, the chemical compound CPTA was administered to
daffodil flowers, which turned reddish within 8 hours due to
lycopene accumulation. However, concomitantly the carotenoid
content was increased 2-3 times over the untreated controls.
Northern blots revealed an increase of mRNA abundance for
several carotenoid biosynthetic enzymes. This result cannot be
explained by the well-known action of CPTA as a lycopene
cyclase inhibitor, but indicates the presence of a novel regulatory
mechanism.

One implication of this finding is that a construct containing only
psy and crtI might be sufficient to install the entire pathway.
Accordingly, reconstructed new single lines have been produced
recently showing again yellow color. Carotenoid quantification
showed again in the best performing segregating F0 line a
carotenoid content of 1.6 µg per gram dry rice endosperm.
Work now in progress aims at increasing the provitamin A
amount by first, identifying the metabolic rate-limiting “bottlenecks”
in Golden Rice. New transformations are underway
employing different endosperm-specific promoters, a codonoptimized
crtI-gene and early pathway genes of the so-called
non-mevalonate pathway of isoprenoid biosynthesis. One further
approach aims at unifying high-iron rice lines with provitamin A
lines since it is known that provitamin A is capable of increasing
the bioavailability of iron.

Further proof-of-concept work aiming at measuring and enhancing
the bioavailability and bioefficacy of the provitamin A are
underway. Golden Rice is not expected to provide 100% of vitamin
A in the diet, but to add to present intakes to reach vitamin
A sufficiency. The current lines are only prototypes and efforts
are underway at minimum to triple the amount of the provitamin
in the endosperm. Certainly, a high priority for research is an
evaluation of the bioavailability and bioefficacy and the pro-vitamin
A contained in Golden Rice. This research has been hampered
in the past by the need to produce a sufficient quantity of
grain (multiple kilograms) for feeding trials in accepted model
systems (pig, pre-ruminant calves, ferrets) in safety greenhouses
in Europe and restrictions prohibiting field trials outside of
greenhouses. However, novel analytical methods have become
available (utilizing HPLC-linked electrochemical detection or
deuterium labeling in combination with HPLC and mass-spectrometry)
to significantly lower the amounts of rice required.
Efforts are currently underway to allow import of Golden Rice
into the U.S. where bioavailability investigations using these
techniques can be conducted.

LEGAL SITUATION AND FIRST STEPS FOR EVENTUAL DISSEMINATION

The development of “Golden Rice” has been made possible by
sequential funding (3 years each) by two agencies, first the
Rockefeller Foundation and then a research program of the
European Community (EC). While funding from the Rockefeller
Foundation was free of obligations, EC funding required the participation
of an industrial partner which would hold rights to
inventions developed during the research. In this case, the industrial
partner was Zeneca (merged recently with Novartis to form
cost would $50 million per year or $500 million over a decade.
Iron fortification costs about 10 cents per person per year.
Reaching 40% of the population (500 million people some of
whom are iron-deficient) with an iron-fortified food would also
cost $50 million per year, or $500 million over a decade.
Recurrent costs of supplementation and fortification remain constant
year after year.

If successful, plant breeding has tremendous leveraging power in
that research output at central facilities (a one-time cost except
for maintenance breeding) eventually may be adapted by national
programs to growing conditions all over the world. For example,
a CGIAR-wide proposal on “biofortification” is proposing to
spend $12.5 million over a decade per crop, or $25 million for
rice and wheat the major staple foods for South Asia. This
amount includes costs of developing nutrient-dense germplasm,
nutritional testing, some adaptive breeding, dissemination costs
for limited areas, and impact studies.

The additional profits made by farmers could well justify the
research investment. A CIMMYT wheat breeder based in
Turkey, where soils are particularly zinc-deficient, has estimated
that, if the zinc-dense seed varieties already available on a commercial
basis in Australia were adapted to growing conditions in
Turkey, Turkish wheat farmers would save $75 million annually
in reduced seeding rates alone (seeding rates could be reduced
from an average of 250 to 150 kilograms per hectare on 5 million
hectares; a ton of wheat might sell for about US$150 on the
world market). This does not even count the benefit of higher
yields.

Howarth Bouis
International Food Policy Research Institute
h.bouis@cgiar.org
+++++++++++++++++++++++++++++++++++++++++++

Biotech crucial for food security

BusinessWorld (Philippines)
November 19, 2001

The country's premier agricultural research institution is urging Filipinos to embrace biotechnology, claiming that it is the practical and viable solution to food security.

Dr. Patricio S. Faylon, executive director of the Philippine Council for Agriculture, Forestry, and Natural Resources Research and Development (PCARRD), recently told reporters biotechnology, particularly the use of genetic engineering in food production, is safe and supported by numerous researches conducted here and abroad.

The method, he said, will be to the advantage of third-world countries such as the Philippines. Right now, we see biotechnology as the solution, because our agricultural lands are dwindling.

Mr. Faylon added those opposed to biotechnology are only a minority. And yet they are the very vocal in their opposition. But if you ask them for scientific researches to back up their claims, they can't give you anything, he said.

Currently, Mr. Faylon said, PCARRD is pursuing four strategies to improve agriculture technology in the country. The agency, he explained, is focused on basic research in high-end technologies such as biotechnology, information technology, geographic information systems, and material science.

PCARRD, he added, is also geared toward the enhancement, promotion, and commercialization of technology; the improvement of research and development (R&D) capability and governance through sustained decentralization; and policy advocacy and formulation.

One of the five sectoral councils of the Department of Science and Technology, PCARRD was created in 1972 to serve as the government's arm in planning, coordinating, evaluating, and monitoring R&D in agriculture, forestry, and natural resources.

Our latest project is the Techno Pinoy program in the municipalities, which aims to equip farmers with the information, tools, and resources they need, he said.

Techno Pinoy, he explained, is an information technology-based farmers' services bureau located in municipal halls around the country. Virtually a one-stop shop electronic library, the facility has complete data on seeds, fertilizers, farming techniques, and industry suppliers.

The agency is also supporting public education in mathematics and science, to arrest the declining admission of public high school students in the University of the Philippines (UP) agricultural school in Los Banos, Laguna.

The projects and research activities, he said, have been streamlined due to a small budget, which has not been increased by Congress since 1994. Yearly, however, PCARRD generates P80 million in research funding from Australia, Japan, United States, and the Food and Agricultural Organization.

PCARRD's pilot genetically modified (GM) food project is the development of a papaya variety resistant to the papaya ringspot virus, found to be widespread in Luzon, Negros, and Leyte.

The virus has resulted in consistently low yields, with the national average at only 17.4 tons per hectare. Mr. Faylon revealed that GM papaya will soon be harvested in Los Banos.

The adoption of virus-resistant papaya, according to PCARRD research, can increase harvests by as much as 41%, amounting to P158 million in revenues annually.

But Mr. Faylon said they are pinning their hopes on breakthrough research on coconut. With experts from UP Los Banos, PCARRD plans to develop a coconut variety that can produce more lauric acid, a component of coconut oil used to manufacture shortening, soap, and other detergents.

Increasing lauric acid by a mere 5% will generate $10 million in additional export revenues, strengthening the Philippine foothold as the world's leading supplier of traditional coconut products.

With the benefits of biotechnology, Mr. Faylon is optimistic that Filipinos will soon recognize the potential of genetic engineering in increasing local crops' production and resistance to diseases. Now that we are in a crisis, many Filipinos will appreciate the value of science.
++++++++++++++++++++++++++++++++++++++++++

... and is safe for humans, says

Business World
November 19, 2001

DAVAO CITY - People need not fear food items from crops improved through research and development, a plant specialist from the University of the Philippines-Los Banos (UPLB) said during consultation on biotechnology held here last week.

Dr. Evelyn Mae Mendoza, program leader of the UPLB Plant Biotechnology Program, said breakthroughs in biotechnology help mankind in coping with issues on food security. These advances also bring positive impact to product development in health and medicine, as well as environment and industry, she added.

Two weeks ago, the Department of Agriculture (DA) conducted its first Consultation on the Rules Governing Biotech Plants and Plant Products. Similar consultation seminars, Agriculture officials said, will also be held in Luzon and Visayas in the coming weeks. The regional DA office said the initial consultation was held here due to the region's fast-growing biotechnology-based agribusiness.

An official of the Bureau of Plant Industry (BPI) said a big number of local firms have set up plant nurseries that apply basic biotechnology process in breeding superior plant varieties. These involve high-value ornamental plants, vegetable and fruit crops that are produced in commercial quantity in the region.

The region's modern nurseries, the BPI official said, earn millions of pesos annually by supplying other commercial-scale plantations in other regions. Unfortunately, these activities have remained unregulated up to now.

During the consultation, plant experts, led by Ms. Mendoza said modern biotechnology covers the application of in vitro nucleic acid techniques including recombinant DNA (deoxyribonucleic acid) technology.

This process gives the subject plant to overcome natural physiological reproductive or recombinant barriers, thus allowing the transfer desirable traits from one organism to another to make better healthful plant products.

During her lecture, Ms. Mendoza cited insulin against diabetes, interferon for treating cancer, vaccine against hepatitis B and other drugs and vaccine against malaria and HIV (human immuno virus)/AIDS (acquired immune deficiency syndrome) as products of biotechnology research.

Gene therapy treatment, where genes are used to combat disease by transferring genes to a patient, is another example of how biotechnology has helped people, she said.

She also defended genetically modified organisms (GMO), which environmentalists worldwide oppose due to their threat to people and the environment.

Ms. Mendoza cited 1998 figures, indicating 3.5 million pounds less pesticides were used for insect- protected varieties of crops. Records from the UPLB Institute of Plant Breeding also show some 44.2 million hectares were planted to GMO crops worldwide last year.

She also noted new agricultural biotechnology products are being developed through tissue culture, gene cloning, genome mapping, marker-assisted breeding and diagnostics. These cover products such as golden rice with high provitamin A, legumes with higher methionine content, cereals with higher lysine and tryptophan, root crops with higher protein content, new varieties of banana to fight hepatitis and diarrhea, she said.

In the Philippines, the regulation of modern biotechnology under the National Committee on Biosafety of the Philippines, DA, Bureau of Agriculture and Fisheries and Products Standards, Department of Health, and Food and Drug Administration.

Agriculture officials, however, noted local biotechnology application has been limited to cloning through tissue culture to produce the best plants.

The banana industry currently uses tissue culture in the region's laboratories and nurseries to maintain the quality of the fruits produced.

With over 30,000 hectares of plantations, the industry needs at least 60 million high-quality young banana plants annually which could cost up to a million dollars if imported from Latin America or Israel.
+++++++++++++++++++++++++++++++++++++++++++++++

'Gene Gun' Blazes Away in Biotech Fight on Famine

By Jeremy Smith
November 17, 2001

LONDON (Reuters) - A designer ``gene gun'' blasting slivers of metal into an innocent soybean plant may sound like a futuristic and far-fetched way to ward off famine by improving the food supply of the world's poorest countries.

So does subjecting stalks of defenseless corn to doses of high-voltage electricity, or bombarding them with sound waves.

But these are just some of the techniques used by scientists striving for more versatility in altering plant cell structures in the controversial research area known as biotechnology, which tries to improve on the precision of natural plant breeding.

Their efforts, they hope, will eventually help the world's poor guard against starvation by beating crop disease and beefing up yields of staple foods such as soy, wheat and maize.

While the bulk of current research aims to improve food plants, the rest of the work is concerned with non-food crops such as cotton, tobacco, ornamental plants and pharmaceuticals.

Even though the term biotechnology refers to a wide range of technologies making use of living organisms, it has now become largely synonymous with genetic engineering -- the controlled alteration of genetic material, or DNA, by artificial means.

Genetic modification (GM) involves exchanging or splicing genes of unrelated species that cannot naturally swap with each other and scientists say the applications are almost limitless.

The species can be vastly different, for example, inserting scorpion toxin or spider venom genes into maize and other food crops as a 'natural pesticide' to deter insects and birds from feeding on them, or fish antifreeze genes into tomatoes.

Gene-splicing has also been used to overcome the sensitivity of fruits such as bananas and melons to lower temperatures so that they can be grown in colder parts of the world.

And scientists believe that plants can be genetically altered to grow cheap vaccines inside them, leading to the use of fruit for painless and plentiful protection against disease.

But how does genetic engineering of plants actually work?

SCIENTISTS USE VARIETY OF GENE-SPLICING TECHNIQUES

Scientists now have a number of techniques at their disposal to move genes artificially into host organisms although only a small proportion of the target cells in the selected plant ever properly incorporate the desired DNA.

One of the most successful ways is to use 'agrobacterium', a soil-dwelling bacterium, as a go-between to introduce genetic information into more than 100 plant species, mainly into wide-leafed plants such as tomato, apple and pear.

A wide variety of plant and tree varieties have been altered by this method, and the technique was used to modify the first genetic plants ever produced -- tobacco, petunia and cotton.

When the bacterial DNA is integrated into a plant chromosome, it effectively hijacks the plant's cellular machinery to ensure that the bacterial population proliferates.

``GENE GUN'' BLASTS PLANT WITH SLIVERS OF METAL

But the most important cereal crops are not affected by agrobacterium and so other methods had to be found. Scientists say their relative success rates are still difficult to judge.

These include ballistic impregnation, also known as ''bioballistics'' or ``biolistics,'' an unlikely-sounding projectile science developed and popularized during the 1980s and used for narrow-leafed plants such as grasses and grains.

A specially-designed ``gene gun'' fires dozens of metal slivers like bullets at target cells. The tiny pellets, usually of tungsten or gold, are much smaller than the diameter of the target cell, and coated with genetic material.

While the shell cartridge is stopped in its tracks by a perforated metal plate, the metallic micro-missiles are able to penetrate into living cells where the genetic material is then carried to the nucleus to be integrated among the host genes.

Gene guns have helped to transform monocot species such as corn and rice. Monocots, meaning monocotyledonae or plants with one cotyledon or seed leaf, comprise a quarter of all flowering plant types. Barley and wheat also derive from monocots.

``Biolistics became quite popular, while the other ways of directly introducing DNA were there all the time but didn't take off quite so much,'' said Professor Peter Caligari at the Department of Agricultural Botany at Reading University, in southern England.

``The monocots, for example the grasses and cereals, were much more difficult to transform using the popular agrobacterium system of transferring DNA than the dicots. But biolistics was a way of getting at the monocots,'' he told Reuters.

Biolistics was still used moderately widely though probably still less than the agrobacterium approach, now developed to be more readily used with at least some of the monocots, he said.

``Agrobacterium at first was fairly limited to dicotyledons although they had also got it to work for monocotyledon plants like corn. But it (biolistics) is just easier,'' said Jane Rissler, senior scientist at the Union of Concerned Scientists, a prominent U.S. environmental group.

PLANTS BLASTED WITH HIGH VOLTAGE, SOUND WAVES

Other transfer methods include creating pores or holes in the cell membrane to allow entry of the new genes. This can be achieved chemically, with sound waves or by using electric currents -- a technique known as electroporation.

With strong electric pulses transmitted on a microsecond basis, minute pores are caused in the plant cells which allows the desired DNA to enter from a surrounding solution.

Sometimes, a genetic scientist will wish to 'silence' a particular gene of an organism to prevent it from being expressed. Gene silencing was first used to create tomatoes with a higher solid content and longer shelf life by halting the natural evolution of an enzyme involved in the ripening process.

Viruses can also be a useful DNA vehicle as they are infectious particles to which a new gene can be added, carrying this gene into a recipient cell while infecting that cell.

And where the host cell is large enough, a fine-tipped glass needle may be enough to inject genetic material containing the new gene, although fewer cells can be treated in this way and the method is much more time-consuming than using a gene gun.

``There's always the thought that maybe a more efficient or more widely applicable single system is out there somewhere,'' said Reading University's Caligari.

``And the more knowledge we get about things, the more possible that perhaps becomes,'' he added.