Mutant beef breakthrough
British government recommends: Cut back on red meat
Meat scare report withdrawn
Public not told about meat recalls, records show
offsite: Official USDA meat recall home page: 1990-1997
18 tons of bad beef sold to Koreans
Europe-US battle over beef hormones
Steven Dickman Science 277, # 5334 26 September 1997, pp. 1922 - 1923Belgium is not exactly known for wide-open spaces and sprawling ranchlands. So farmers there had to learn to do more with less. Over the last 30 years, they have bred a strain of cattle--the mighty Belgian Blue--that gives 20% more meat per animal on roughly the same food intake as ordinary animals. Indeed, the cattle develop such bulging muscles that in extreme cases they have trouble walking and the calves are so big they have to be delivered by cesarean section. Now, three research groups have independently uncovered the genetic cause of this "double-muscling" trait, a discovery that may lead to meatier strains, not just of cattle, but of other agriculturally important animals as well.
In the September issue of Nature Genetics, a pan-European team led by Michel Georges of the University of LiËge in Belgium reports that double muscling is caused by a mutation in the bovine version of a recently discovered gene that makes a protein called myostatin. The other two groups, one co-led by Tim Smith of the U.S. Department of Agriculture (USDA) lab in Clay Center, Nebraska, and the other by Sejin Lee of Johns Hopkins University, also found that the myostatin gene is mutated in Belgian Blues and have linked mutations in the gene to double muscling in a second breed of cattle, the Piedmontese, as well.
Discovered just 4 months ago in mice by Lee and his graduate student Alexandra McPherron, myostatin normally serves to limit skeletal muscle growth. Apparently, the mutations block its activity and the animal's muscles grow larger--but without harming meat quality. While some other cattle breeds are also abnormally well muscled, presumably because of as-yet-undiscovered mutations, the muscle fibers in those animals are thicker than normal, toughening the meat. In contrast, the muscles of animals with myostatin mutations have larger numbers of normal-size fibers. Indeed, says Smith, meat from the Belgian Blue is "so tender even round steaks fall apart on the grill." Nevertheless, the meat is lower in fat than that from ordinary breeds.
Given those effects of myostatin mutations, it's not surprising the gene is attracting attention from agricultural scientists. "This is the first gene identified in cattle that controls a combination of muscle size and tenderness," says molecular geneticist Mike Bishop of ABS Global, a biotech firm in Madison, Wisconsin. He notes that beef palatability, as well as yield, might be improved by introducing myostatin gene mutations into cattle or by finding drugs that turn down the gene's activity. Such strategies might also lead to meatier pigs, chickens, and turkeys, as the Lee team found that the myostatin gene has relatives in these and other farm animals.
The meandering cow path to this discovery started in Belgium in the 1950s, Georges says. Cow breeders there, who were under economic pressure from cheaper imports and high production costs, wanted to increase their yields and began to select for the double-muscling trait, which had been reported as early as 1807. Before long, nearly every beef cow in Belgium was a purebred double-muscled animal.
The sequences revealed that the gene from the double-muscled animals carries an inactivating mutation--an 11-base pair deletion--that results in "virtually complete truncation" of the active region of the protein, Georges says. That lifts the normal repression of muscle growth by myostatin and opens the way for extra brawn.
The Lee team used a similar approach to come up with the Belgian Blue gene. The researchers then guessed that double-muscled Piedmontese cattle would also have a mutated myostatin gene, and when they cloned it, that's what they found. Smith, working with John Baff's team at AgResearch in Ruakura, New Zealand, took a somewhat different tack, using the mouse gene to first find the gene in normal bovine DNA and then in Belgian Blues and Piedmontese, where they, too, found mutations. Similar mutations could also add bulk to other farm animals, for the Lee team has found the gene in all nine species they examined, including mammals, such as the pig, and birds, including chickens and turkeys.
Despite the interest in using the myostatin gene to improve beef production, researchers warn that it may be a difficult task. One possibility is to use either conventional breeding or genetic engineering to introduce the Belgian Blue mutation into other breeds. So far, however, U.S. breeders have only rarely attempted to do this, even by conventional breeding. This is partly for practical reasons. The need to deliver calves by cesarean section is a serious handicap in the United States, where cattle herds are larger and roam over much wider areas than they do in Belgium.
That problem might be overcome if researchers can find a less extreme myostatin mutation or identify another gene with a less drastic influence on muscle mass, allowing the calves to be delivered naturally. But there are also worries about whether the public would accept genetically engineered beef. The cattle industry has until now shied away from funding research into transgenic animals for human consumption. "They perceive it as too sensitive and risky an area," Smith says.
Another possibility would be to find some drug that can turn down myostatin activity in animals with the normal gene. And then there may be other genes that can be manipulated. Researchers in at least four countries are mapping the cattle genome, and reproductive physiologist Vernon Pursel of the USDA research labs in Beltsville, Maryland, says "we are getting to the point where there will be a number of genes" like myostatin identified in the near future. Extra helpings of tasty meat at essentially no cost could prove hard to resist.
September 25, 1997 Times
LONDON -- People who eat more than 5 ounces of red meat a day should cut back their consumption to reduce the risk of cancer, the British government said Thursday.
The recommendation was included in a report that the Committee on Medical Aspects of Food and Nutrition Policy, an influential advisory panel, had been preparing for more than three years into the dietary aspects of cancer. The panel said even people who eat less red meat than that should consider reducing their intake. Other researchers have already established strong links between a high intake of animal fat, mostly from meat and cheese, and higher rates of cancer and heart disease.
"The average consumption of red and processed meat should fall; Those with intakes at or above the current average of around 90 grams/day (about 8-10 portions per week) should consider a reduction; and those with high intakes above around 140 grams/day (about 12-14 portions per week) should reduce their consumption," the Department of Health said.Asked why COMA was advising people to eat less red meat, a ministry spokesman said:
"Because members of COMA believe that at that level the risk is of an increased likelihood of cancer, especially colorectal (bowel) cancer."Only part of the report was released. The ministry said the full report, which COMA discussed at a meeting Wednesday, would be published as soon as possible. The "Times" newspaper reported that the report's launch was canceled at the last minute, either because the panel disagreed about the wording or because ministers got cold feet about publishing a report likely to do further damage to the British meat industry.
The industry was hard hit by the disclosure last year that so-called mad cow disease, which rots the brain, could probably be transmitted to humans. Consumer confidence in meat has also been sapped by fatal outbreaks of the E. coli bacteria.But the ministry said clarifications to the COMA report were needed before it could be published in full so people could understand the recommendations easily. Health Secretary Frank Dobson said he had the full support of cabinet colleague Jack Cunningham, the agriculture minister, for the recommendations announced Thursday.
September 25 1997 BY NIGEL HAWKES, SCIENCE EDITORA GOVERNMENT report warning that people who eat a lot of red meat are at greater risk of cancer has been delayed at the last moment.
The report, three and a half years in preparation, was due to be published today by the Department of Health. But arrangements to launch the report were hastily cancelled as the committee responsible met amid reports of disagreements about its contents.
A second report on the same subject by the World Cancer Research Fund will be published today, but no date has been set for the official report by the department's committee on the medical aspects of food policy (COMA).
The report, produced by a panel led by Alan Jackson of Southampton University, draws from more than 1,000 research papers on links between food and cancer. It is believed to have concluded that people who eat more than 140g of red meat a day run an increased risk of cancer. Normal consumption is between 85g and 90g a day.
The suspicion about the delay in producing the report was that either ministers had cold feet over publishing a document likely to do further damage to a meat industry already reeling from the E coli and BSE scandals, or that internal divisions within COMA had surfaced over the precise wording of the report.
September 25, 1997 APBRUSSELS The European Union vowed Thursday to continue, at least until December, its eight-year battle with the United States over its ban on imports of beef produced with the aid of growth-promoting hormones. The European Commission, which represents the 15 EU states on trade issues, said it would appeal against a ruling by the World Trade Organization that the ban violated world trade rules.
In a document to be submitted to the WTO on Oct. 6, the European Union will argue that the WTO had misinterpreted two key international agreements on food safety standards and ignored scientific evidence that growth-promoters could present a risk to human health, commission sources said. Crucial to the EU's argument is that the international accords -- the Sanitary and Phyto-Sanitary Agreement and Codex Alimentarius -- allow individual countries or blocs to set higher standards.
"Otherwise there is a risk of food safety standards falling to the lowest common denominator," said one commission official.The WTO is expected to rule on the EU's appeal by the end of December. Even if the EU loses, the commission has indicated it will not accept the contested beef, opting instead to compensate the United States. The European Union maintains that there is significant scientific evidence to suggest that beef produced using growth promotors are carcinogenic. But this is contested by the U.S., where hormones have been widely used in beef production for 30 years.
Washington had challenged Brussels' 1989 ban on imports of animals and meat treated with six growth hormones through the WTO, complaining that the action cost it 100 million dollars in lost European sales. A panel set up to hear the complaint issued a final report upholding the U.S. stance in August.
The United States maintains there is no scientific proof that the hormones pose danger to humans and claimed the EUwas seeking to protect domestic meat producers from more competitive imports. Brussels for its part argues that the measures it imposed seven years ago are justified because the effect of hormones on health health has not been [dis]proven.
In a debate on the issue, three scientists, including Samuel Epstein, head of the Cancer Prevention League, have testified to EU officials that beef treated with natural and synthetic hormones could cause cancer despite persistent U.S. denials.
September 25, 1997 APWASHINGTON -- Since 1990, as much as 20.2 million pounds of meat and poultry has been recalled because of contamination and the public was never told, Agriculture Department records show.
In one nonpublic 1993 case, Quaker Oats Co. recalled more than 1.8 million pounds of chili because of potential contamination with sand. More than 400,000 pounds was not recovered, according to an Associated Press review of the records.
In another large case that had no public notice, Bil Mar Foods of Zeeland, Mich., recalled more than 1.2 million pounds of cooked beef because of possible bacteria problems in 1994. Almost 900,000 pounds of that beef was not recovered.
In all, 142 of the 262 federal meat and poultry recalls between 1990 and 1997 were not publicly announced, the records show. They do not show where the meat was distributed before the recall.
But the Agriculture Department usually does not make any public announcements about recalls involving products that were distributed to restaurants or school cafeterias or were sitting in warehouses or on trucks and were not sold at retail to consumers.
"It would not be identifiable by the consumer because they don't have it in a package that they can identify it," Jill Hollingsworth, a USDA deputy administrator involved in recalls, said Wednesday.But consumer advocates say it is time for the Agriculture Department to rethink its policy, pointing out that someone could become ill from eating a bacteria-laced burger at a restaurant or a school cafeteria and never know the product had been recalled.
"It is not enough to just tell the restaurant there's a problem. It does make sense for the public to be notified," said Caroline Smith DeWaal, food safety director at the Center for Science in the Public Interest. "Consumers need to know."The Agriculture Department held a public meeting Wednesday to discuss its current recall policies and hear from advocates such as DeWaal, along with representatives of meat industry groups. Catherine Woteki, USDA's undersecretary for food safety, said the session would help the agency determine whether changes such as wider public notification are necessary.
"Our primary motivation for those policies is protecting the public health," Woteki said in an interview. "If there are things that we could do that would better protect the public health, we would certainly change our policy."Meat and poultry products involved in the unpublicized recalls had many problems, according to USDA records. Some were recalled because of possible bacterial contamination, others because they contained small pieces of bone, metal or plastic. And others were improperly labeled or had defective containers, the USDA records show.
It is USDA policy not to issue a public recall notice unless consumers are likely to have purchased a meat product and might still have some on hand. That was the case last month when Hudson Foods Inc. recalled 25 million pounds of ground beef because of possible E. coli contamination. Some of that beef was sold at retail. Instead, officials work privately within the food service industry to determine who has control of the bad product and to get it out of the system, said the USDA's Hollingsworth.
Industry officials said meat processors are the ones that would lose if all recalls were publicized, even those in which public health is not endangered. They said companies have every reason to work with government to remove the bad meat.
"There's a tremendous economic and business incentive to take adulterated product off the shelf as soon as possible," said Jim Hodges of the American Meat Institute.Some
industry officials expressed dismaythat USDA has recently posted details of every meat and poultry recall since 1990 on an Internet site -- whether it was made public at the time or not.
"It has a potentially damaging effect on the companies involved," said Bob Hibbert, an attorney for the Eastern Beef Processors Association.Agriculture Secretary Dan Glickman has already asked Congress for authority to issue mandatory meat and poultry recalls and for tougher civil penalties. A bill that would do that, however, has not been introduced
Reuter Information Service September 26, 1997WASHINGTON - U.S. Agriculture Department officials said Friday they were investigating reports that South Korea found E. coli bacteria in a shipment of frozen U.S. beef. The officials said they were surprised by the South Korean government announcement earlier Friday that it found the deadly bacteria, O157:H7. The beef would have had to pass USDA inspection before it entered the export market, they said.
Three USDA officials said the report was the first sign of any problem with U.S. beef that was sold to South Korea. One of the first questions for the USDA review, officials said, would be the identity of the supplier. South Korea's Agriculture Ministry said the bacteria, which can cause food-borne illness, was found in a shipment of 18.8 tons of frozen beef purchased by Korea Cold Storage Co. Ý