Gene escape is seriously bad news

March 2022

In 2005 the scientific view was that "... the movement of transgenes beyond their intended destinations is a virtual certainty" (quoted in Ellstrand)

Gene escape from GM crops is something environmental activists have done a lot of shouting about. However, although regulatory lip-service is paid to it in risk assessments, the consequences of walk-about genes seem to be swept under the carpet. The biotech mindset is that artificial genes (including edited ones) will only do what they've been constructed to do wherever they end up: for example, herbicide-tolerance genes will be neutral in the absence of the herbicide, pesticide-generating genes specific to a target pest will be neutral in the absence of that pest, and anyway artificial genes won't find their way into a comfortable, alternative plant host often enough for it ever to matter.

In real-life, not all GM plants are growing neatly in fields [1] and, where wild relatives grow within pollinating distance of GM plants, gene-pollution of their weedy cousins has been widely reported. Although studies on the ecological consequences of this are thin on the ground, what little information we have is ominous.

GM in sewage

December 2019

One concern about GM crops which European regulators have always taken seriously, is the possibility of the horizontal gene transfer of artificial antibiotic-resistance genes from GM food plants into strains of bacteria which cause human and livestock disease.

Antibiotic-resistance has been described as medicine's climate change: a modern day plague [1].

Historically, most commercial GM crops incorporated antibiotic-resistance genes as part of their development procedure, and many 'newer' GM crops on the market are little more than stacked versions of the old. Although there's been a shift to the use of other marker genes in GM crops for the US market, antibiotic-resistance genes continue to be present especially in GM consumed in 'lower resourced countries'.

A tale of microbes, your gut and disease

December 2019

Scientists who have escaped the distortions of the reductionist mindset, in which 'life' is a mixture of chemicals dictated by genes, are beginning to recognise that organisms have two genomes*: the 'primary' genome is inside cells and is responsible for cell structure and function; the 'secondary' genome may consist of more genes than the primary one and is contained in the wealth of microbes inside and outside the organism, effectively a dynamic interface between the environment and the individual.

*The genome is the total complement of DNA including genes and other gene-regulating sequences in the individual (US National Library of Medicine)

There's increasing awareness that the quality, proportions and diversity of microbe species in our gut is closely connected to health and disease. Disturbances in our digestive tract flora have been linked to numerous chronic diseases, for example, allergies, autoimmune disorders (such as type 1 diabetes), arthritis, obesity, cardiovascular problems, cancer, learning and memory impairment, anxiety, stress, depression, autism and dementia. Our gut bugs play a leading role in neutralising a huge range of environmental pollutants before they can harm us, and in keeping pathogens at bay.

Natural artificial organisms - whatever next!

December 2019

Definitions of 'transgenic':

1. containing genetic material artificially transferred from another species
2. having genetic material, in all cells, that includes a gene or DNA sequence transferred by means of genetic engineering from a genetically unlike organism.

Note the need for an artificial or engineered transfer, specifying that a human action as an essential feature.

Readers of GM-Free Scotland will be aware that genetic engineers don't 'move' genes from one species to another: they build DNA constructs using adapted, man-made DNA templates gleaned from multiple organisms plus the odd totally artificial sequence all cobbled together. The DNA creation is multiplied up in GM bacteria and then used, either to create a GM bacterial plant pathogen or to coat molecular missiles for a gene gun, which are used to force the novel DNA into the target organism.

Captured DNA

November 2019

The pre-eminent biotech breakthrough of the new millennium has undoubtedly been gene-editing.   

For commercial applications, gene-editing is attractive: one, it's simple, two, it's precise in regard to what and where the edit is, three, above all it doesn't insert foreign DNA.  This last attraction is the most important because it's used to claim that gene-edited organisms are non-GM, and that the edits simply mimic what can happen in nature, and that they therefore need no special regulation.  

Apart from number one above, the 'simple' bit, all the rest of these attractions have been proven wrong. 

Natural excuses to avoid GM safety testing

March 2019

The biotech lobby is coming up with all sorts of fancy arguments to avoid regulation of new DNA-altering techniques which don't involve the insertion of novel genes (protein-coding DNA) into an organism.

Industry-led claims abound that small mutations are naturally present in all organisms, as is the presence of horizontal gene transfer between organisms. The story continues to say that because it is equivalent to 'natural', edited DNA is nothing to worry about. It goes on: organisms arising from intentional DNA-editing are similar to those produced by old, random mutagenesis techniques (such as irradiation). Since the latter have never been regulated, there's no reason to do so with the 'new' version. Moreover, DNA-edited organisms are so 'natural' that their identification is impossible and they are, therefore, untraceable, making regulation impossible to enforce. And, even if the changes are found, no one can tell if the mutation is a result of a natural DNA mutation or a deliberate one. In fact, in our Environment Secretary's view, since Mother Nature is already giving us genetic mutations and horizontal gene transfer, biotech scientists are merely giving Her a helping hand.

All this 'reasoning', however, seems to be more to do with commercial expediency than with science.

Medicine's climate change

February 2019

"Antibiotic resistance in our pathogens is medicine's climate change: caused by human activity, and resulting in more extreme outcomes".(Kurenbach).

These 'extreme outcomes' include conservative estimates that tens of thousands of Americans die each year due to previously-treatable, but now antibiotic resistant, infections. Warnings of this threat go back half a century.

Take horizontal gene transfer seriously - now

February 2019

The risk to health from artificial antibiotic resistance genes being used as markers during the creation of most GMOs was recognised in Europe back in the 1990s. However, lulled by mathematical modelling suggesting horizontal gene transfer (HGT) would never be significant in a complex, natural environment, the problem wasn't taken too seriously [1].

Creeping grass with creeping toxins

August 2018

Pure creeping bentgrass and nothing but creeping bentgrass is a must-have for golf-courses.

Its fine texture and ability to 'creep', forming a dense, even cover, are prized by groundskeepers. For professional tournaments with big money at stake, weeds are a no-no. Anything other than 100% bentgrass makes any kind of putt on a green unreliable.

Back in 2003, when agribusiness giants Scotts Miracle-Gro and Monsanto trialed RoundupReady bentgrass which needed nothing more than a squirt of Roundup herbicide to keep it pristine, they thought they were onto a winner. In fact, it turned into a giant headache which continues to this day [1].

Herbicides stimulate antibiotic resistance

February 2018

Multi-antibiotic resistance in pathogenic microbes is a serious, and increasingly common, occurrence. It complicates the treatment of infectious diseases, makes health care more expensive, and can be a death-sentence for the patient.

We know that, once a pathogen evolves a mutant gene for antibiotic resistance, this can be passed to other microbes by horizontal gene transfer. Long ago, concerns were raised that the artificial antibiotic resistance genes often added to GM crop plants as markers during their development could fuel the emergence of antibiotic resistant pathogens. No one seems to be tracking whether this is a reality, but bugs can make themselves resistant to toxic medicines by other means, and counter-intuitively these 'other means' can be fuelled by herbicide-tolerant GM crops.

When bacteria are exposed to a toxin, their first line of defence is to switch on their own pumps to rid themselves of it. If this physiological mechanism can kick in fast enough (before the toxin kills it), the bug can make itself resistant to an antibiotic for as long as necessary.

The link to GM crops is that herbicidal chemicals and their spray co-formulants are also toxic to bacteria. Tests on the glyphosate-based herbicide used on most current GM crops, and on dicamba and 2,4-D which are up-and-coming replacements for glyphosate, plus the 'surfactants' added to all three to aid penetration into the weeds, showed they all trigger the toxin-pump mechanism in three commonly pathogenic bacteria. 'Surfactants' are detergents, classed as 'inerts' by US Environmental Protection Agency (EPA), and are ignored in safety assessments. However, the bacteria clearly don't find them 'inert'.

GMM contamination

September 2017

Many food and feed additives, produced once upon a time by chemical synthesis or extraction from natural sources, are now derived from fermentation of GM micro-organisms (GMMs).

EU rules require that such additives in the final product must be pure. This means that the GMM itself (alive or dead) or any artificial DNA inserted into it must have been removed.

Accordingly, no special labelling is required for GMM-derived additives. Also, there is no regulatory control system in place for the products of GMMs. It is assumed the company marketing the additive will verify the absence of the GMM and its novel DNA in the final substance.

Besides use as food processing aids and as a means of conferring artificial qualities on food products, GMM-derived additives include 'health' promoting substances, such as vitamins.

In 2014, EU regulators were notified that a German official enforcement laboratory had detected live GM bacteria in a consignment of 'riboflavin' feed additive from China.

A new GM maize with questions

January 2015

A summary of a scientific opinion on an entirely new GM maize was published by the European Food Safety Authority (EFSA) in 2015. Under scrutiny was Syngenta's Maize 5307 for food and feed use (not cultivation). The maize has two novel genes.

Even in summary form, the EFSA assessment raises some interesting questions.

New Zealand's GM cow disaster

January 2016

Ever since Dolly the cloned sheep was born in Scotland in 1996, biotech scientists have had their sights on GM livestock.

'Cloning' can now refer to several procedures, but generally involves removing a nucleus from the cell of an animal with desired characteristics and inserting it into an egg cell whose own nucleus has been removed.  The restructured egg is then stimulated to divide and form an embryo which is inserted into the womb of a surrogate mother.  If all goes well, the pregnancy goes to full-term and a healthy, fertile offspring ensues. 

For genetic engineers, that brief availability of the cell nucleus of a future animal is a golden opportunity to insert a gene.

The procedure involves at least three animals: the nucleus donor, the egg-cell donor, and the embryo recipient.  Because the success rate is low, it also involves multiple embryos and multiple sets of cell donors and surrogate mothers.  Add to this the veterinary surgeons, drugs, field-station facilities and staff, specialist laboratories and, of course, biotech scientists.  Clearly, cloning doesn't come cheap.

Artificial horizontal gene transfer (HGT)

January 2016

"Genetically modified” or "GM" is the term settled on by politicians to describe the artificial creation of genes (genetic engineering) and the artificial change of DNA in an organism (genetic transformation). 

Even in the earliest days, GM DNA was never as simple as a single protein-coding 'gene'.  Scientists soon realised that their isolated DNA needed all manner of adjustments and extra bits if it were to work at all in its new environment, and some of their creations don't code for a protein at all but were found to alter the function of the natural genome around them in useful (to man) ways. 

For twenty years the public have been listening to claims that 'GM' is 'safe', but the proof of GM safety shifts with the tides.  And consumer distrust has continued unabated. 

The big new propaganda event of last year was the 'discovery' of a "naturally GM" food crop [1]. 

Sweet naturally GM potatoes

July 2015

Sweet potatoes. Photo Creative Commons

A newly published study has shed a fascinating new light on the effect of crop domestication on the evolution of crop plants.

Analysis of the genome of the sweet potato revealed stable incorporation of functional DNA from a possibly ancestral species of bacterial plant pathogen, Agrobacterium rhizogenes. No such horizontal gene transfer was detected in wild relatives.

Sweet potato is one of the oldest domesticated crops and has been found in archaeological remains dating back 8,000-10,000 years.

Bio-P potatoes

July 2015

Non-GM potatoes. Photo Creative Commons

The latest UK Government GM venture has been announced: GM potatoes designed to satisfy consumers, farmers and food processors.

First off the planned production line in a few short years will be potatoes containing a stack of novel genes: three to combat late fungal blight, two to ward off nematode soil pests, two to switch off the production of sugars and an amino acid which together have a nasty habit of producing a toxic derivative when heated, and one to switch off the enzyme which turns raw potatoes black when they're bashed.

Future GM potatoes are planned which will have increased nutrients and which don't sprout in storage. Also under investigation are weird potatoes for industrial starch production and vaccines-in-a-spud.

Novel potatoes for biofuel production are not to be developed as these would compete for food-growing land and are not considered the socially-preferred option.

Herbicides may promote superbugs

June 2015

Photo Creative Commons

Evidence of another insidiously harmful effect of Roundup herbicide has been published. Scientists in New Zealand presented findings which extend to Roundup and two other common commercial herbicides (Dicamba and 2,4-D) which, like Roundup, are sprayed on crops genetically transformed to tolerate them and are used in parks, roadways and gardens.

It seems antibiotics and herbicides don't mix.

Genetic firewalls

June 2015

Photo Creative Commons

Proteins are made up from chains of standard building blocks termed 'amino-acids'. Amino acids can react with each other to form a chain, and have a side-arm which can be any one of some 24 specific molecules each having its own particular properties. The important properties of the amino-acid side-arms include, for example, size, shape, reactivity, bonding capacity and electrical charges. It's the specific sequence of amino-acid side-chains which dictate the properties of the protein they make up, for example, how it folds into a 3-dimensional shape, what chemicals or chemical groups it can react with or bind to, how easily it can be digested, and its toxicity.

 

Chemical engineers can create an almost infinite variety of artificial amino-acids by attaching novel side-arms. Unnatural amino-acids aren't any use to natural living organisms, but biotech scientists have hit on them as a basis for terminator technology for their genetically modified organisms (GMOs). The principle is that an essential enzyme (see below) is cleverly redesigned to incorporate a novel amino-acid while still preserving its enzymic function. 

Genetically modified humans?

February 2015

All the myths and assumptions of a "vanishingly small" risk of horizontal gene transfer from GM food into humans have now been blown apart.

In the prevailing culture of denial, regulators and industry have peddled a science-free rationale on how impossible any harm from horizontal gene transfer is.

But now we know:

• DNA in food is not digested down to an amorphous mix of its nucleic-acid subunits in the gut: it can survive in strands (up to and including as big as genes) which can, and do, pass into the body
• Dietary DNA can circulate to all tissues, where it can be incorporated into the genome if it has even a short sequence similar to the genome of the consuming organism
• Most DNA isn't a gene which codes for protein but is regulatory in nature and highly active in altering gene function; unlike genes, such DNA can consist of very short sequences.
• Some DNA is naturally prone to mutation and change
• Some DNA is mobile and can jump from one location in the genome to another, or into another genome

The pseudo-science which claims that the DNA carefully crafted by human hand to work in soya or maize couldn't possibly affect human consumers is definitely wrong in the case of 80% of currently commercialised GM crops. And possibly in all of them.

Fit as a weed

September 2014

 

Wild rice. CC photo by Denrdoica cerulea on Flickr

The vast majority of GM crops now being grown commercially have had a gene inserted to make them resistant to glyphosate herbicide.

 

After spraying with glyphosate, the yield of the GM crop is protected because the weeds competing for nutrients are killed.

 

Gene escape from glyphosate-tolerant crops into wild relatives has never been considered an important problem because unless the wild GM derivatives are sprayed with the herbicide, they will have no special fitness advantage and no reason to run riot. But, this 'wisdom' has been challenged by a team of Chinese scientists.

 

Glyphosate kills plants by inactivating an enzyme, 'EPSPS'*. EPSPS is vital to a number of key metabolic processes because it's responsible for generating a class of essential amino acids (the building block of proteins). These amino acids are vital to the formation of, for example, the plant's supportive material (lignin), plant growth hormone, and a huge range of immune-system substances, which together can account for as much as 35% of a plant's biomass.