Cloned food scare: where’s the beef?

Last week, after 10 years of study and backed up by 1,000 pages of data and analysis, the US Food and Drug Administration (FDA) concluded that food from cloned animals is safe to eat (1). Instinctively, Greenpeace, organic farmers and the Daily Mail – an Axis of Reaction against the modern world – responded that such food is dangerous. In truth, cloned food is safe and could provide significant advantages for farmers and consumers.

A clone is simply an organism produced from the DNA of another organism, so identical twins are clones of a single fertilised egg. Far from being the freakish creations of crazed scientists, clones are abundant in nature and cloning has been used by man in agriculture for thousands of years.

Any plant propagated by cutting is a clone. Grapevines and olive trees, among the most ancient cultivated foodstuffs, are grown exclusively by cloning, as are bananas, potatoes, apples, pears and peaches. Every gardener practices cloning when taking and planting a cutting of a favourite shrub. Such cuttings usually produce stronger and healthier plants than the original and act to ‘reinvigorate’ the plants’ genes. For many species, it is sexual reproduction via seeds that causes loss of potency and susceptibility to disease.

The first mammal cloned from an adult was Dolly the sheep, in 1996 at the Roslin Institute in Scotland. But amphibians (such as frogs) were cloned in the 1950s and, in the 1990s, clones were produced from animal embryos. Over the past decade, laboratories around the world have successfully cloned mice, rats, rabbits, cattle, pigs, sheep, goats, deer, horses, mules, cats and dogs.

It is the analogy with plants that made the cloning of animals such an important scientific objective. Selective breeding over hundreds of years may result in an animal with attractive attributes (eg, high muscle/fat ratio in beef cattle, low fat/milk ratio in dairy cows or resistance to common diseases) but when that animal is mated with one of the opposite sex, the offspring may inherit a host of unwanted attributes. Selective animal breeding is a continual struggle to maintain desirable traits while avoiding the undesirable.

Animal cloning offers the prospect of more certainty to farmers, by providing breeding stock with guaranteed physical traits. Cloning also provides a guarantee of food quality to consumers. For example, it will eventually be possible to ensure that cows in a dairy herd give birth only to female offspring – saving the waste of young males sent to slaughter or exported live for veal production. When birds have been cloned (which has not happened yet), egg producers will be able to guarantee that only female chicks are hatched; currently male chicks are simply discarded.

Cloning is, however, a major threat to those with vested interest in preventing agricultural progress.

In the vanguard of anti-cloning propaganda is the Soil Association, a lobby group that exists to freeze agricultural technology in 1946 (when ‘organic farming’ was invented by British aristocrat Lady Eve Balfour). The Soil Association promotes ‘organic’ food in the UK and charges farmers to certify their ‘organic status’. Although the market for organic food in Britain is small (less than two per cent of consumption), the Soil Association is well-connected through a network of titled landowners (including Prince Charles and Lord Melchett), media celebrity hobby farmers (such as BBC personalities Jonathan Dimbleby and John Humphrys) and TV cooks Jamie Oliver and Hugh Fearnley-Whittingstall. The last two have been engaged in a high-profile campaign to encourage shoppers to buy organic chicken – despite advice from the Food Standards Agency that organic poultry contains much higher levels of pathogenic bacteria salmonella and campylobacter, which are especially dangerous to children and the elderly (2).

Soil Association declarations on ‘food safety’ issues are repeated in the British media as gospel. ‘Cloning involves ghastly and invasive techniques’, was the Association spokesman’s predictable comment on the FDA’s report. He added: ‘How do they know the food is safe when the studies haven’t been done?’ (3)

In fact, the FDA has gathered all available data from cloning experiments – published and unpublished – and subjected it to intense scrutiny and peer review. ‘Peer review’ is the new buzzphrase for environmentalists (though few recognise it when they see it) and the FDA has helpfully included all the reviewers’ comments on its website.

The FDA also publishes ‘Cloning Myths’ – which cannot have been consulted by any of those who campaign against cloned animal products, since it comprehensively disproves each of the scare stories:

• Cloned animals are damaged or weak

  As with any new technology, cloning suffered from early teething problems. An adult cell’s embryonic capability is ‘switched on’ by treatment with cell-stimulating chemical factors and by an electrical charge; these cause its genes to ‘revert’ to a state equivalent to those in a newly fertilised egg, from which an adult can develop. Before this technique was perfected, there was a high failure rate of implanted embryos; some calf and lamb fetuses grew too large during pregnancy and had serious birth defects (known as Large Offspring Syndrome – LOS). LOS was also seen in the early days of other assisted reproductive technologies such as IVF. Rates of LOS in lamb and cattle are now very low and LOS has not been seen in pig or goat clones.

• Clones are born at the same age as the cell donors, so don’t live long

  This misconception arises from the findings about telomeres – long sections of chromosomes that may function as a kind of clock. Telomeres tend to be longer at birth and shorten as the animal ages. Dolly’s telomeres were slightly shorter than those of her (genetically identical) cell donor, which led some to believe that her normal lifespan would be reduced. Dolly exhibited no signs of abnormal aging despite regular health screening. She developed arthritis, which was probably detected only because she came under such close scrutiny, but the disease was well-controlled with medication and was certainly not ‘crippling’ as Greens claim.

  Sadly, Dolly had to be euthanised at the age of six because she contracted (from another sheep) the incurable virus that causes sheep pulmonary adenomatosis (SPA) in which the lungs fill with tumours – completely unrelated to the cloning process.

Don’t expect cloned lamb chops or milk from cloned cows anytime soon. Cloned animals will mainly be used to supply farmers with reliable, disease-resistant breeding stock. But do expect to hear a great deal more nonsense from the ‘back to the dark ages’ unholy alliance of right-wing newspapers, green Luddites and vested interests among wealthy farmers who will not tolerate competition from a technology that truly offers good, safe food and massive welfare benefits for our farmyard animals.

Rob Johnston is a freelance writer on the environment, health and science.

(1) Animal cloning: first draft risk assessment, US Food and Drug Administration

(2) ‘…we think that extensively-reared chickens are likely to come into more frequent contact with Campylobacter which is ubiquitous in the environment. We also believe that it will be very difficult to maintain high levels of biosecurity in the extensive production setting. Given the fact that an important reason why consumers buy organic is because they consider organic produce to be healthier and better for you, it is important that consumers are aware of this risk’, Food Standards Agency: Advisory Committee on the Microbiological Safety of Food, Second Report on Campylobacter [pdf]; ‘Salmonella Prevalence in Free-Range and Certified Organic Chickens’. Bailey, J.S. et al. Journal of Food Protection Volume 68, Number 11, November 2005 , pp. 2451-2453(3).

(3) EU gives green light for cloned food to go on sale in UK shops, This is London, 11 January 2008