ngin - Norfolk Genetic Information Network
Date:  6 November 2000


Chicken items originated Joyce@GEN:

1.    Genetic chickens get DNA copyright tag - url
2.    New super chickens fuel GM food row
3.    Crack open an egg and cure a disease
4.    Go-ahead to breed GE sheep

1.    Genetic chickens get DNA copyright tag 

The Guardian, 31 July 2000 by James Meek, science correspondent 
Biotech firm plans to create strain with extra large breasts for more meat,2763,348884,00.html

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2.     New super chickens fuel GM food row
From an article in the Sydney Morning Herald, August 1, 2000, as cited in AnimalNet.

A U.S. biotech company plans to genetically engineer a chicken with an extra-large breast which will yield more meat, and then insert a DNA tag to stop anyone breeding without permission. If successful, AviGenicswould be one of the first to put GM meat on US supermarket
shelves, opening up new tensions with Europe over genetic engineering in food. AviGenics, based on the campus of the University of Georgia, is already one of three US companies racing to turn poultry into drugs factories - adding human genes to create "transgenic" birds, which would then produce human proteins such as insulin in their egg whites. AviGenics claims to have already created transgenic roosters that have passed on the human gene for a substance called alpha interferon, used
to treat hepatitis and certain cancers.  The company hopes to use the same technology to create a chicken for everyday eating.

Instead of adding human genes to make birds lay drug-rich eggs, genes would be added, or chicken genes removed, to give the birds bigger breast muscles, faster growing rates or greater disease resistance. To keep proprietorial control over these valuable new animals, AviGenics is working on a novel kind of trademark, a DNA sequence which would be introduced into the chicken's genes and handed on to the bird's offspring.
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3.    Big breakfast - Crack open an egg and cure a disease
       From New Scientist, 13 November 1999

WHY did the geneticist cross the chicken? To turn it into a cheap pharmaceuticals factory, it seems. Comical as it may sound, two companies are planning a pilot test of drugs in eggs laid by genetically engineered chickens.

GeneWorks of Ann Arbor, Michigan, announced this month that it has a flock of between 50 and 60 genetically engineered birds. Some carry a gene that enables them to make a human growth factor in their eggs, while others produce a human antibody.

Although the company will not name the proteins, it says that both have great potential for treating disease. According to its chief operating officer Steve Sensoli, GeneWorks has deals to make 14 proteins for six drug companies around the world.

Meanwhile, AviGenics of Athens, Georgia, has produced a human interferon for treating cancer in its flock of birds. It claims to have a slight lead on its rival because it has already managed to pass on the interferon gene to further generations of birds. With hens producing an average of 200 eggs each per year, and 100 milligrams or more of a drug in each egg, both companies believe the yields could be large and lucrative.

The companies smuggle genes into the birds using harmless forms of viruses that are engineered so they cannot replicate. The gene that makes the protein is inserted in the virus.

GeneWorks uses the reticulo endotheliosis virus as a ferry. The company uses a genetic switch that restricts production of the protein to the egg white. "We put it in a one-day-old chicken embryo by microinjecting it into a cavity called the blastoderm," explains Sensoli. He and his colleagues hope that some virus reaches primordial cells in the blastoderm which develop into sperm and eggs, so the gene for the protein can be passed down to future generations of chickens, rather than having to repeat the injection in each generation. But the company can already harvest the proteins from hens that have been injected and next year plans to open a production plant capable of making "metric
tonnes" of protein.

AviGenics already has transgenic cockerels producing new generations of GM birds. "They're very busy," says Carl Marhaver, the company's president. AviGenics uses the avian leukosis virus as a gene shuttle. "We microinject it into the pronucleus in the egg yolk," says Marhaver. The gene is then expressed in all the chicken's cells. AviGenics plans to contract out production and protein purification to companies which already produce vaccines in chicken eggs--a long-established practice in the pharmaceuticals industry.

Helen Sang, a chicken biotechnology researcher at the Roslin Institute in Edinburgh is encouraged by the companies' work. "It is good progress, and proof of principle," she says. Sang, who is developing a virus-free method of shuttling genes into chickens, points out that the technology
has been in development for a decade (New Scientist, 20 November 1993, p 19). But she is disappointed that neither company is keen to publish openly in the scientific literature.

Sensoli says the work is too commercially sensitive to publish, and all but two of the proteins under development are unknown outside the companies that discovered them. "It's a shame we can't blow our horn a bit more," he says.
Andy Coghlan
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4.    Go-ahead to breed GE sheep - New Zealand Herald - 1 November 2000
        by Kevin Taylor [shortened]

Quiet paddocks at Ruakura near Hamilton will soon host a flock of genetically modified sheep with "double muscles," bred to aid research into muscular disease and heart attacks.

The Environment Risk Management Authority (Erma) has approved AgResearch's application to breed up to 100 sheep in the world-first  research, which could benefit patients of muscle-wasting diseases such as muscular dystrophy and Aids.

The sheep will be missing the gene myostatin, which regulates muscle growth in most mammals.
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