更新時間 2011年 1月 13日, 格林尼治標準時間20:13
英國科學家研究培育出了世界上第一批轉基因雞。這種經過基因改造的雞不會傳播禽流感。
研究人員在科學雜誌上發表文章說，他們在雞的基因中植入了一個自然界不存在的人工基因。
科學家們還說，這種技術從原則上說可以用來防止任何家畜感染病毒。
研究人員表示，這一科學上的突破有可能大大提高食品生產同時降低成本。
不過家禽業人士表示在食品生產商考慮使用這種技術前還需要做更多的研究以及要得到消費者的接受。
http://www.bbc.co.uk/zhongwen/trad/uk/2011/01/110113_brief_gm_chicken.shtml
英國科學家研究出不會傳播禽流感的基因改造雞
14.01.2011 05:22
英國科學家研究出全球首批經基因改造的雞，令雞隻即使染上H5N1禽流感，亦不會傳播病毒，避免大規模擴散，人類亦可以安全食用這些雞，專家下一步會研究對禽流感病毒有抵抗能力的雞，以及將技術用於農場內其他動物。 負責研究的劍橋及愛丁堡大學專家指，經基因改造的雞，仍然會因為感染禽流感死亡，但測試顯示，即使在同一個雞欄，其他雞隻亦不會受到感染；專家又說，一旦病毒變種，有關的基因改造技術仍然發揮作用。分析指，人類較少感染禽流感，但一旦染上，死亡率相當高。世衛資料顯示，由零三年起，共有五百一十六宗人類感染禽流感個案，當中三百零六人死亡。
http://www.881903.com/page/zh-tw/newsdetail.aspx?ItemId=320971&csid=261_367
英科學家稱創造出轉基因抗禽流感雞
更新時間 2011年 1月 13日, 格林尼治標準時間22:33
英國科學家宣稱已經通過轉基因手段培育出全世界第一批不傳播禽流感的雞。
這個研究小組在《科學》雜誌上發表文章說，他們的研究結果表明，創造各種各樣的抗病毒家畜家禽是完全可能的。
這些科學家採用的方法是，把一個人造基因植入培育的雞，從而讓禽流感病毒的一個微小部分進入雞的細胞。這些雞受到了感染，但是釋放出的病毒對其他禽類無害。
科學家相信，他們所實施的基因改造對雞和食用這些雞的人類都是無害的。
科學家表示，從原則上講，這種技術可以用於所有家禽家畜和所有的疾病，最終發展出完全抵禦病毒類疾病的飼養動物。
但是，英國家禽飼養業對這一消息作出了謹慎的回應。英國禽類飼養協會負責人布拉德諾克說，在食品生產商有可能考慮使用這一技術之前，需要大量的研究，需要就長期影響作出評估。
英國的一些家禽養殖者還表示，最好的辦法是嚴格管理農場，避免飼養動物生病，而不是創造什麼轉基因動物。
按照英國的法規，任何轉基因技術投入這類用途都需要經過食品標準機構的批准，而這個機構必須首先進行全面和嚴格的評估。
http://www.bbc.co.uk/zhongwen/trad/uk/2011/01/110113_gm_chickens.shtml
世界上第一隻抗流感轉基因雞'被創造'
World's first flu-resistant GM chickens 'created'
By Pallab Ghosh
Science correspondent, BBC News
13 January 2011 Last updated at 19:01 GMT
UK scientists have created the world's first genetically modified chickens that do not spread bird flu.
Writing in Science journal, the team says their work demonstrates it is possible to create a variety of GM farm animals resistant to viral diseases.
The research team inserted an artificial gene into chickens; this introduces a tiny part of the bird flu virus into chicken cells.
These birds become infected but render the virus harmless to other poultry.
The team believes that the genetic modification they have introduced is harmless to the chickens and to people who might eat the birds.
Professor Helen Sang of Edinburgh University told BBC News that genetic modification is potentially a much better way of protecting against diseases than vaccination because the GM technique works even if the virus mutates.
"It will protect a whole flock from avian influenza infection. This is really exciting because bird flu is a real challenge to poultry production and if it were introduced to poultry breeding it would protect our large scale production flocks from avian inlfuenza," said Professor Sang.
廣泛保護
Broad protection
The researchers say that, in principle, the technique could be used to protect any farm animal from any disease. The eventual aim is to develop animals that are completely resistant to viral diseases.
Genetic modification could be an alternative to vaccination, scientists say
轉基因可能是一種替代疫苗注射的選擇，科學家們說
According to co-author Dr Laurence Tiley, from the University of Cambridge, UK: "Agricultural selective breeding has made huge improvements on productivity of many livestock - but it's reaching the point where it's now limited.
"And the GM technologies allow you to introduce novel genes that don't exist in nature but are based on our detailed knowledge of the molecular biology of viruses. We can specifically target these viruses to prevent them from replicating."
The researchers say think the technology has the potential to boost food production and reduce costs.
"There's going to be a real problem in feeding the world as the population increases," says Professor Sang.
"As the demand for animal products increases and it's going to get increasingly expensive and we are looking at different ways to tackle that problem."
GM techniques could also have benefits for human health, according to Professor Sang. If fewer animals are carrying viruses there is a lower chance of them mutating into a form that would be deadly to humans and so create a pandemic.
謹慎的歡迎
Cautious welcome
But the news received a cautious welcome from the poultry industry. Peter Bradnock of The British Poultry Council said more research was needed to assess the long term impact on farm animals before food producers would even consider using the technology.
Even then, companies would have to assess the likely reaction from consumers: "We have to have a big debate as to whether society wants to have GM animals even for this very good potential benefit," he told BBC News.
And Tim Elsdale, who is an organic farmer in East Sussex, said it was better to adopt good farming practices to avoid animals getting diseases in the first place than to create GM farm animals.
"We don't suffer much from animal diseases on this farm," he said.
"Organic methods of husbandry doesn't encourage disease if the animals are well spaced enough. They live in a natural environment and they eat normal food then a lot of diseases that are prevalent on conventional farming would not be apparent to us".
If the food and farming industry did want to use GM technology in this way in the UK, they would need to seek prior approval from the Food Standards Agency (FSA). The FSA would conduct a full detailed safety evaluation before any of this GM produce could enter the market.
In addition to that, produce would need to be labelled so that consumers would be able to make a choice about the food they eat. If there were an application, the authorisation process could be carried out in a matter of months.
The FSA's Chief Scientist, Dr Andrew Wadge said it would be interesting to see if the debate over GM animals would go the same way as the debate over GM crops:
"I do think it's interesting that so far with GM technology it's not really a benefit for consumers and wouldn't it be interesting if we had produce that did offer a benefit?
"For example, food safety for us is about a bacteria found in chickens called Campylobacter which makes 500,000 people ill each year.
"If we could develop a GM chicken that is resistant to Campylobacter it would be very interesting indeed to see how consumers saw that technology and whether it was a technology they would be willing to embrace".
http://www.bbc.co.uk/news/science-environment-12181382
抗癌雞蛋生產
Anti-cancer chicken eggs produced
Last Updated: Sunday, 14 January 2007, 18:49 GMT
UK scientists have developed genetically modified chickens capable of laying eggs containing proteins needed to make cancer-fighting drugs.
英國科學家已發展轉基因雞能產下雞蛋，含有需要的蛋白質作抗癌藥物。
GM chickens could be a route to faster, cheaper drugs轉基因雞可能是一個途徑往更快、更便宜的藥品
The breakthrough has been announced by the same research centre that created the cloned sheep, Dolly.
The Roslin Institute, near Edinburgh, says it has produced five generations of birds that can produce useful levels of life-saving proteins in egg whites.
The work could lead to a range of drugs that are cheaper and easier to make.
Professor Harry Griffin, director of the institute, told the BBC: "One of the characteristics of lots of medical treatments these days is that they're very expensive.
"The idea of producing the proteins involved in treatments in flocks of laying hens means they can produce in bulk, they can produce cheaply and indeed the raw material for this production system is quite literally chicken feed."
Roslin has bred some 500 modified birds. Their existence is the result of more than 15 years' work by the lead scientist on the project, Dr Helen Sang.
But it could be another five years before patient trials get the go-ahead and 10 years until a medicine is fully developed, the Roslin Institute cautioned.
抗病毒的方法
Anti-viral approach
Therapeutic proteins such as insulin have long been produced in bacteria; but there are some complex proteins that can only be made in the more sophisticated cells of larger organisms.
Scientists have successfully made a range of these molecules in the milk of genetically modified sheep, goats, cows and rabbits.
The work at Roslin shows it is now possible to use chickens as "biofactories", too.
A number of GM animals are now being used as drug factories目前一些轉基因動物被用作藥品工廠
Go-ahead for 'pharmed' goat
Some of the birds have been engineered to lay eggs that contain miR24, a type of antibody with potential for treating malignant melanoma, a form of skin cancer. Others produce human interferon b-1a, which can be used to stop viruses replicating in cells.
The proteins are secreted into the whites of the eggs. It is a fairly straightforward process then to extract and purify them.
Dr Sang said the team was highly encouraged by the level of the birds' productivity, but further improvements were required.
"We're probably getting a high enough productivity if you want to make a very active protein like interferon, but not enough yet if you want to make an antibody because people need large doses of these over long periods; so one of our next challenges is to try to increase the yield in egg white," she told BBC News.
更廣泛的作用
Wider role
Chickens had some advantages over other animals for "pharming" because their lifecycles were shorter, said Dr Sang.
"Once you've made the transgenic birds, then it's very easy; once you've got the gene in, then you can breed up hundreds of birds from one cockerel - because they can be bred with hundreds of hens and you can collect an egg a day and have hundreds of chicks in no time," she explained.
The Roslin research is part of the Avian Transgenic Project, a joint venture with biotechnology firms Viragen and Oxford BioMedica.
Details of the latest work are to be published this week in the US journal Proceedings of the National Academy of Sciences (PNAS).
The Roslin team also expects its engineered chickens to provide new insights into aspects of reproductive biology.
It says the ability to modify birds' embryos will allow researchers to study fundamental processes that control the very early development of vertebrates.
It is just over 10 years since the Finn Dorset lamb called Dolly was born at the institute.
She was the first mammal to be cloned from an adult cell - making her a genetic replica of a six-year-old ewe. She was put down in 2003 after contracting a common lung disease.
http://news.bbc.co.uk/2/hi/science/nature/6261427.stm
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