Anti-allergen milk... with added allergens

November 2012

Cow
Photo of non-gm cow by JelleS on Flickr
The U.S. media has made much of the latest “impressive (GM) technical feat that won plaudits in the biotechnology world”. This impressive feat is the creation by scientists in New Zealand of a GM cow called Daisy.

Daisy's milk is missing 'β-lactoglobulin', a “key” protein often responsible for triggering allergies. In the first year of life, as many as two or three in every hundred infants are allergic to this protein.

Rather than report the huge ethical, scientific and safety issues surrounding the novel cow, journalists have chosen instead to lament the “hopeless logjam” caused by the U.S. government in its failure to rush GM animal products to market. Also due to the regulatory incompetence which, it seems, is having “a chilling effect on animal biotech efforts”, GM animal research is being abandoned or transferred overseas. One Canadian scientist is quoted as saying his GM pigs have had to be banked in cold storage until “societal attitudes improve”.

Before blaming the government and public for the lack of GM super-animals in the world, perhaps the journalists should have considered the matter in more depth.

Genetically modification of animals poses overwhelming ethical questions.

The suffering of the surrogate dams which bear the GM offspring, and of the mutant offspring themselves are unacceptable. Both suffer physical trauma, health problems and, more often than not, death. For example, to produce one cow with altered milk, 57 attempts gave rise to only five successful transformations, four successful pregnancies, and a single live female calf which had to be delivered a month prematurely by caesarian section due to hydroallantois (water accumulation caused by a defective placenta). At only 7 months of age, Daisy was treated with hormones to induce lactation. The technique is cruel.

Safety considerations surround the unpredictable nature of all genetic transformations, and even more so the biotech technique used in the making of this GM cow. The engineered DNA inserted is not a gene, but produces small molecules of a similar coding molecule, micro-RNA. This micro-RNA is a gene regulator and its action switches off the cow's problem-protein gene off.

Data on micro-RNA molecules are the latest thing to roll off the genome-analysts' benches. The DNA which produces them is thought to comprise as much as 20% of the genome, while the actual protein-coding genes amount to only some 2%.

These controlling elements are not only more abundant than genes, but they exist in more variant forms, they interact with each other, and a single micro-RNA may have a multiplicity of actions. In the bigger picture, the parts of the genome influenced by a micro-RNA may not lie anywhere near it, and micro-RNA action is thought to extend to communication between cells. The whole micro-RNA scene has been described as “stunningly complex”, “almost incomprehensible” and “almost inconceivably intricate”. One scientists said graphically “My head explodes at the amount of data”.

Given the nature of micro-RNA described above super-imposed on the wealth of dodgy manipulations needed in cloning, is it reasonable to expect that we can control the outcome? Well consider this: the “impressive technical feat” called Daisy was born without a tail.

What can (or should have been) predicted in the quest to eliminate this major protein from cow's milk, is that the cow's body knows it needs that protein. If it can't make β-lactoglobulin, it makes more of other proteins to compensate. In this case, one of the 'other' proteins in the GM milk turns out to be casein, which is another well-known allergy-trigger. One US pediatrician said that usually children are allergic to a variety of milk proteins, including casein, so taking out one of them won't help. In fact, the higher casein therefore presents “probably the worst-case scenario for most of our patients”.

One of the biggest unknowns is the effects that artificial micro-RNA might have inside our bodies. These regulatory molecules are small, and can survive digestion: they have been found circulating in the blood-stream from where they can reach any organ. Their action is not species-specific: they have been shown to be able to interfere with the function of liver cells (see BEWARE NON-GENETIC ENGINEERING - November 2011)

OUR COMMENT

In light of all of the above, is the problem with GM animals really regulatory bumbling or societal attitudes?

Hypo-allergic milk is clearly intended to be targeted at the young. How many parents, knowing all the above concerns would feed it to their children?

Moreover, even the underlying concept of eliminating one “key” protein from milk is clearly faulty.

The protein compensation seen in the GM cow when an attempt was made to artificially change the levels of a single protein may well be present in some form in all GM animals and plants. In other words, the generation of 'novel' proteins by a GM organisms might extend very far beyond the man-made one, with no guarantee of safety.

At the moment, GM animal produce are nowhere near the horizon, but keep an eye out for them.

SOURCES
  • Rosie Mestel, Scientists fret over FDA slowness on genetically altered animals, Los Angeles Times, 1.10.12
  • GM Calf Research Ignores Ethical Problems, Raises Safety Concerns, GM Freeze News Release, 3.10.12
  • Lin Zhang et al., 2011, Exogenous plant MIR168a specifically targets mammalian LDLRAP1: evidence of cross-kingdom regulation by microRNA, Cell Research
  • Breakthrough study overturns theory of 'junk DNA' in genome, Guardian, 5.09.12
  • Gina Kolata, Bits of Mystery DNA, Far From 'Junk,' Play Crucial Role, New York Times, 5.09.12
  • Ian Sample, GM cow designed to produce milk without an allergy-causing protein, Guardian, 1.10.12

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