SAN FRANCISCO – U.S. poultry growers have a chicken-and-egg dilemma.
For decades, people who raise chickens for dinner tables have been honing their “selective breeding” skills and have gotten pretty good at growing the fattest bird possible.
But meatier and faster-growing birds lay fewer eggs, and prolific egg-layers tend to be skinny. Chicken producers would love to increase production of meatier chickens by minimizing the influence of the skinny genes.
Origen Therapeutics and AviGenics are among biotech companies considering this dilemma as they pursue the perfectly engineered bird. And their solution is sure to rile a number of advocacy groups, because it involves not just genetically modified food but also cloning and embryonic stem cells.
The idea is to create identical copies of eggs with desirable traits that can roll off assembly lines by the billions. The hatched chickens would be identically disease-resistant and grow and eat at the same exact rate.
This goal has yet to be fully embraced.
Biotechnology opponents fear that genetically modified organisms are little understood, that the potential for harm to humans is great. Animal rights activists argue that the science simply provides a more efficient way to harm chickens.
“We strenuously object to the mass production of chickens in the first place,” said Jessica Sandler of the People for Ethical Treatment of Animals. “Animals aren’t machines. Genetic engineering will only exacerbate the problem.”
But with an estimated eight billion chickens bred in the U.S. for food annually, these biotechnology companies see an industry ripe for their technology.
Besides, they argue, engineering chickens is no different from selectively breeding them, as the industry does now.
“There is very little that is natural” in the current breeding process, said Robert Etches, vice president of research at Origen.
To prove his point, he grabs from his office bookshelf the American Poultry Association’s “American Standard of Perfection,” which is wedged between “The Life of Birds” and “The Poultry Production Guide.”
The book lists and pictures more than 800 different breeds of chickens. Etches points to a photograph of the Chinese Silkie – a chicken with a white afro covered in fluffy hair-like feathers that resembles a poodle.
“Many things have been bred at the hand of man,” he said, snapping the book shut.
Etches and his colleagues at Burlingame-based Origen Therapeutics Inc. aim to create a robotic assembly line that injects embryonic stem cells from meaty chickens into millions of eggs to duplicate nearly identical birds.
The process does not involve any genetic manipulation.
“We call it metacloning,” said Origen chief executive Robert Kay.
Embryonic stem cells are identical “blank slates” formed in the first days of pregnancy that blossom into all the cells that make up an animal.
Scientists studying all forms of embryonic stem cells – including the human version – believe they can someday manipulate these primordial cells into any adult tissue of their choosing.
Origen hopes to breed bigger chickens faster by extracting embryonic stem cells from the fastest growing and biggest chickens and injecting them into fertilized eggs of the skinnier egg-laying chickens.
Origen scientists hope they can coax the embryonic stem cells to take genetic control of the skinny chicken’s egg, suppressing the parents’ genetic expression, and create a meaty chicken.
It’s not nuclear transfer – the best-known cloning technique – but Kay said the company someday hopes to consistently create chickens that are nearly carbon copies of the embryonic stem cell donors.
Kay would not explain Origen’s methods, and said the technology is still years from fruition.
At the moment, the company’s dozen researchers cut open the eggs and manually add embryonic stem cells to embryos, creating chicks with the genes of four parents.
Ultimately, they hope to automate the process without opening the eggs.
In July, the National Institute of Science and Technology awarded Origen and another biotech company, Embrex of Research Triangle Park, N.C., a joint $4.7 million research grant. Embrex’s role is to develop the industrial injection assembly line that will employ Origen’s technology.
Embrex already makes machines that can inject vaccines into 50,000 eggs an hour.
In Athens, Ga., meanwhile, scientists at AviGenics are attempting to get around the egg problem by cloning chickens destined for digestion with favorable traits such as large breasts. AviGenics does employ nuclear transfer, the technology that brought the world Dolly the sheep.
Anthony Cruz, an AviGenics vice president, said the company has yet to successfully clone a chicken and won’t predict when that may occur.
“There is still a lot of work to do,” he said.
Indeed, these biotechnology companies readily concede they face years of technical and regulatory obstacles before they can revolutionize the poultry industry.
And first, they must convince chicken and egg producers their technology is needed – and that it won’t, for example, backfire and create genetically uniform animal populations that could be wiped out with a single fatal epidemic.
Besides the technical and regulatory issues, public reception to genetically modified food has been tepid at best.
“Our industry is always looking for efficiencies,” said Richard Lobb, a spokesman with the Washington D.C.-based National Chicken Council. “But I think our companies are taking a wait-and-see approach. There are many hurdles still to overcome.”