Archive for October, 2013

GMOs: poisons that will kill our children, or harmless foods?

29 October, 2013

I think I hung my colours out long ago in this “controversy”, but let us just be clear:

I DON’T BELIEVE ANY OF THE GMOs CURRENTLY BEING FARMED WORLDWIDE POSE ANY THREAT TO HUMANS OR STOCK ANIMALS AT ALL.  NONE!  NOR DO MOST BIOLOGICAL SCIENTISTS WHO ACTUALLY UNDERSTAND WHAT GENETIC MANIPULATION OF PLANTS ENTAILS.

Is that clear enough?  No ambiguity there?  Good!  Because the people who have taken poor Fair Lady magazine to task recently, mainly on their Facebook page, for daring to publish an article saying the same thing, would have you believe otherwise.  By relentless recycling of discredited animal feeding studies, reiteration of untruths, canards and plain lies, and by personal attacks on anyone expressing an alternate view.

Title page of the article

Title page of the article

I don’t think that Fair Lady will complain if I reproduce the title page, because I think their article is a reasoned, well written and factual exploration of the topic – which is a LOT more than I can say for most of the comments about the article.  Which includes gems like this:

“Oh dear Fairlady Magazine has made a BIG mistake!!!! Writing an article like this could put them out of business. I will never buy a Fairlady Magazine again and neither will any of my family. Stick to fashion Fairlady. Let Farmers Weekly publish an articles on GMO’s!!!! GMO’s are killing people. It’s not an exaggeration. It is proven, published, peer-reviewed fact. How many people do you know with cancer? Can you count on one hand or two. Ask yourself why. Maybe you could ask well-Informed People who are Fully Aware of the Irreversible Damage unleashed by Toxic GMOs on Earth.”

Now the problems that I have with the kinds of attacks on GMOs that are exemplified by these responses, are the following: these are the assertions that

  1. EVERYTHING is Monsanto’s fault
  2. ALL GMOs are toxic / poisonous
  3. There is ample evidence of harm to both animals and humans

All three of these straw men are, of course, rich in taurine excreta.  In the first place, while Monsanto may well have started the ball rolling on a big scale, and owns patents and seed rights on much of the early and simple one-trait GMOs, they do NOT own everything, and are NOT responsible for many of the recent developments still coming down the developmental pipeline – which are considerably more sophisticated than the ubiquitous herbicide-resistant or Bt-producing maize or cotton.  These would include plants resistant to various viruses, bacteria and fungi, plants engineered for higher nutrient / vitamin content (eg: Golden Rice and golden bananas), and drought- and salt-tolerant plants.

As for toxicity, NO GMO can be released if there is convincing evidence of toxicity in animal feeding trials, which HAVE to be conducted for each new “event”, or novel GMO.  I have sat on panels in SA which have assessed applications by seed companies to grow / produce GM crops, and I can tell you that this is a major feature of any application.  Where non-expert people often get confused is the fact that certain crop plants have been engineered to make insect-specific toxins normally produced by the bacterium Bacillus thuringiensis.  These are collectively known as “Bt toxins”, and the ones used as insecticides are specific for narrow ranges of related insects, and most often for lepidopterans – which include moths and butterflies.  Now the larvae of particularly certain species of moths are major agricultural pests, and include agents such as maize stalk borer and the cotton bollworm – and from Wikipedia:

“Spores and crystalline insecticidal proteins produced by B. thuringiensis have been used to control insect pests since the 1920s and are often applied as liquid sprays”.

That’s right: crystalline protein masses extracted from live bacteria and live spores of bacteria used to be sprayed around as pest-control agents.  Everywhere!  Moreover, from Wikipedia again,

“Because of their specificity, these pesticides are regarded as environmentally friendly, with little or no effect on humanswildlifepollinators, and most other beneficial insects and are used in Organic farming“.

Yes, really: actual Bt toxin, and actual spores that can develop into live bacteria, can be used in organic farming.  Now why would anyone have a problem with a technology that LIMITS exposure of the environment to a bacterial toxin, and most especially, to live bacteria, by containing the protein within the plant tissues?  Moreover, the amount of Bt in the edible seeds of maize is minimal, and people don’t eat cotton – so we are left with possible effects on wildlife, and cattle which eat the green parts of the plants.  And no-one has ever  shown any deleterious effects of Bt in GM plants on non-target organisms.  Oh, there was the Pusztai report, which claimed to have shown that snowdrop lectin-containing transgenic potatoes were toxic to mice – but this elicited the following comment:

“The [British] government’s Advisory Committee on Novel Foods and Processes(ACNFP) has dismissed Dr Pusztai’s findings as inconclusive and irrelevant due to serious doubts concerning the design of the study. The particular type of potatoes on which Dr Pusztai conducted his experiments would never have been approved for food use. Indeed, the ACNFP stated that had an application been submitted on the basis of the data collated from this flawed study, it would have undoubtedly been rejected”

A nice exploration of the pervasive effects of bad publicity following publication of bad science was published recently: this was “When bad science makes good headlines: Bt maize and regulatory bans“, in Nature Biotechnology.  These authors state that

“Numerous laboratory toxicity studies and field experiments, as well as years of field observations in countries where Bt maize is cultivated, have provided evidence that the Cry1Ab protein expressed in Bt maize does not cause adverse effects on arthropods outside the order Lepidoptera (butterflies and moths), the group that contains the target pests. Supporting data have been analyzed in reviews and meta-analyses”

Another point of contention is herbicide-resistant plants, which again, have not convincingly been shown to be toxic.  I say convincingly, because anti-GMO activist will immediately quote “the Seralini study” which purportedly showed deleterious effects on lab rats fed transgenic maize producing a protein which detoxifies the herbicide glyphosate as well as the herbicide itself – to which I reply by inviting you to read this rather damning report by the European Food Safety Authority, which opens with the following statement:

“Serious defects in the design and methodology of a paper by Séralini et al. mean it does not meet acceptable scientific standards and there is no need to re-examine previous safety evaluations of genetically modified maize NK603″

Now I will remind everyone that this is an agency which is NOT in Monsanto’s pocket – or anyone else’s – and which upholds high standards in safeguarding the general public.  As do the US Department of Agriculture (USDA) and the Food & Drug Administration of the USA, which also have no problems with GMOs (FDA statement; USDA information).  Here is a another comprehensive refutation of the “evidence of toxicity” of glyphosate-resistant soybeans, an unpublished study that is widely quoted by anti-GM lobby.

As for “ample evidence of harm” – I can only refer you to what we biotechnologists would regard as an authoritative source, which is the journal Nature Biotechnology.  In a recent article on GMOs entitled “How safe does transgenic food need to be?” by Laura DeFrancesco, the author asks the question:

“Why, after transgenic products have been in the human food chain for more than a decade without overt ill effects, do these doubts persist? And will it ever be possible to gather sufficient evidence to ameliorate the concerns of skeptics and the public at large that these products are as safe as any other foodstuff?”

Further on, she says:

“Critics and proponents of genetically modified organisms (GMOs) alike agree that genetically modified foods have failed to produce any untoward health effects, and that the risk to human health from foods contaminated with pathogens is far greater than from GMOs” [my emphasis]

I don’t think I need to belabour the point further: I am hopelessly compromised, in the eyes of some of the more rabid activists, by being a biotechnologist at all, and especially – Gasp!! – BECAUSE MY LAB MAKES GMOs!!!  However, if that makes me more amenable to believe actual evidence-based findings, rather than unsubstantiated media hype, then so be it.

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A Risky Science Communication Environment for Vaccines

14 October, 2013

See on Scoop.itVirology News

Controversy over childhood vaccinations is an instance of what might be styled the “science communication problem”—the failure of compelling scientific evidence to resolve public dispute over risks and similar facts (1). This problem itself has been the focus of scientific study since the 1970s, when psychologists began to investigate the divergence between expert and public opinion on nuclear power. Indeed, the science of science communication that this body of work comprises can now be used not just to explain controversy over risk but also to predict, manage, and in theory avoid conditions likely to trigger it. The example of childhood vaccinations illustrates these points—and teaches an important practical lesson.

 

Ed Rybicki‘s insight:

It is indeed alarming that the public in developed countries should be increasingly anti-vaccination, when the situation in developing countries is so different.  I suppose it is because of their success that there is now such diminished risk in the wealthier parts of the world, that people (wrongly) start to assume there are greater risks from vaccination than from the diseases they protect against.

And wrongly, because while diseases like measles might be ALMOST eradicated in much of the world, any slip in coverage can result in its very rapid reintroduciton into places like the USA and the UK, where numbers of cases have been rising recently.

I suppose all we can do is try to convince those around us that the knee-jerk "vaccines are evil" responses of the dumber civilians are simply stupid – and that for everything our children receive vaccinations for, the risks of wild-type disease are still greater than vaccine complications.

See on www.sciencemag.org

Scientists find new botulinum toxin, withhold genetic details

12 October, 2013

See on Scoop.itVirology News

Scientists have discovered the first new type of botulinum toxin in 40 years, and in a highly unusual move, they are keeping the toxin’s genetic sequence data secret for now so that no one can make it in a lab before an effective antitoxin can be developed.

Until now, Clostridium botulinum was known to produce seven types of toxins, all of which cause paralysis by blocking neurotransmitters in humans and animals. The last one was discovered in 1970.

Ed Rybicki‘s insight:

What equine excreta!?  Really??  "We found a new botulinum toxin, but we won’t tell you what it is – but it can’t be neutralised by CDC antitoxins"??  Isn’t THAT enough information for your dedicated cave-dwelling biotechnologist to go out and look, via next-gen sequencing, for novel Clostridium strains??  Oh no – does what I’ve just written constitute a dangerous disclosure?  Should I censor myself??

Seriously, this pious "we have this cool new discovovery but can’t tell you what it is because nasty people may make it" mentality is just ridiculous.  What makes it MORE ridiculous is telling people about it at all in that case: no-one ever hear about reverse engineering, or simply going looking for something becaue you now know it’s there?

See on www.cidrap.umn.edu

Mammals Have Similar Virus-Killing Power [as] Seen In Plants

12 October, 2013

See on Scoop.itVirology News

Previous research has shown that plants and invertebrates use an immune response called the RNA interference(RNAi) pathway to build a weapon against a viral infection.

Two new studies from scientists at the University of California, Riverside have found that a similar pathway exists in mammals, but it is typically suppressed by viral proteins. The study researchers said if this suppression could be lifted, it would open the door to a completely new way to treat a viral infection.

In the studies, the scientists were able to remove the suppressor protein from the virus. This allowed laboratory mice to quickly eliminate an infection from the Nodamura virus from their system using the RNAi process, which dispatches small interfering RNAs (siRNAs) to kill the disease.

Ed Rybicki‘s insight:

I know of Shou-Wei Ding from many years ago, when he worked on the plant (and original) CMV and the 2b gene: it has long been suspected that mammals should be similar to their plant and insect cousins; it is heartening to see that in fact they are.

Of course, the mammal folk will now quickly cream all the kudos for this, and the Nobel will NOT go to a plant or insect virologist!

See on www.redorbit.com

US Congress shutsdown CDC, also other unimportant agencies

6 October, 2013

See on Scoop.itVirology News

So the US government is likely being shutdown, which will suspend the work of many government agencies, including the Center for Disease Control (CDC). But, fair citizens, I reassure you – in its wisdom, the US Congress has decided that the military’s salaries will be excluded from the shutdown.

With all due respect to military personnel, this is ludicrous. The US military is by far the world’s largest, there is little likelihood of any major war (the last great power war was in 1953), and no sign of minor wars starting, either. Suspended salaries may be bad for morale and long term retention, but they aren’t going to compromise US military power.

Contrast with the CDC’s work. The world’s deadliest war was the second world war, with 60 million dead, over a period of years (other wars get nowhere close to this). The Spanish flu killed 50-100 million on its own, in a single year. Smallpox couldn’t match that yearly rate, but did polish off 300-500 million of us during the 20th century. Bog standard flu kills between a quarter and a half million every year, and if we wanted to go back further, the Black Death wiped out at least a third of the population of Europe. And let’s not forget HIV with its 30 million deaths to date.

Ed Rybicki‘s insight:

What he said….

See on blog.practicalethics.ox.ac.uk

Progress stalled on coronavirus

5 October, 2013

See on Scoop.itVirology News

A year on from the first reported human case of infection with Middle East respiratory syndrome coronavirus (MERS-CoV), the world still has few answers to the most pressing question from a public-health perspective: what is the source of the steady stream of new cases? Only with this information can the outbreak be controlled.

Ed Rybicki‘s insight:

Strange how nationalism can trump common sense – in the face of something like MERS.

See on www.nature.com

The Plant Host Can Affect the Encapsidation of Brome Mosaic Virus (BMV) RNA: BMV Virions Are Surprisingly Heterogeneous

4 October, 2013

See on Scoop.itVirology News

Brome mosaic virus (BMV) packages its genomic and subgenomic RNAs into three separate viral particles. BMV purified from barley, wheat, and tobacco have distinct relative abundances of the encapsidated RNAs. We seek to identify the basis for the host-dependent differences in viral RNA encapsidation. Sequencing of the viral RNAs revealed recombination events in the 3′ untranslated region of RNA1 of BMV purified from barley and wheat, but not from tobacco. However, the relative amounts of the BMV RNAs that accumulated in barley and wheat are similar and RNA accumulation is not sufficient to account for the difference in RNA encapsidation. Virions purified from barley and wheat were found to differ in their isoelectric points, resistance to proteolysis, and contacts between the capsid residues and the RNA. Mass spectrometric analyses revealed that virions from the three hosts had different post-translational modifications that should impact the physiochemical properties of the virions. Another major source of variation in RNA encapsidation was due to the purification of BMV particles to homogeneity. Highly enriched BMV present in lysates had a surprising range of sizes, buoyant densities, and distinct relative amounts of encapsidated RNAs. These results show that the encapsidated BMV RNAs reflect a combination of host effects on the physiochemical properties of the viral capsids and the enrichment of a subset of virions. The previously unexpected heterogeneity in BMV should influence the timing of the infection and also the host innate immune responses.

 

Ed Rybicki‘s insight:

Interesting!  I have a fondness for BMV; I have probably purified more of it than just about anyone else alive, and probably have more of it purified and on the shelf than anyone as well.  But I did not know this…nice to know someone’s still working on it, and finding new and interesting things!

See on www.sciencedirect.com

The Gemini Virus

1 October, 2013

See on Scoop.itVirology News

Available in: NOOK Book (eBook), Paperback, Hardcover, Audiobook. This science-based thriller from Wil Mara will chill you to your coreBob Easton thinks he has a cold. Before he dies in agony, four days later, he infects dozens of people.

Ed Rybicki‘s insight:

Of course, there are already geminiviruses in good standing: these infect plants rather than people, and do not make people cough, but make plants feel rather uncomfortable.

See on www.barnesandnoble.com

Oral immunogenicity of porcine reproductive and respiratory syndrome virus antigen expressed in transgenic banana

1 October, 2013

See on Scoop.itVirology News

Porcine reproductive and respiratory syndrome virus (PRRSV) is a persistent threat of economically significant influence to the swine industry worldwide. Recombinant DNA technology coupled with tissue culture technology is a viable alternative for the inexpensive production of heterologous proteins in planta. Embryogenic cells of banana cv. ‘Pei chiao’ (AAA) have been transformed with the ORF5 gene of PRRSV envelope glycoprotein (GP5) using Agrobacterium-mediated transformation and have been confirmed. Recombinant GP5 protein levels in the transgenic banana leaves were detected and ranged from 0.021%–0.037% of total soluble protein. Pigs were immunized with recombinant GP5 protein by orally feeding transgenic banana leaves for three consecutive doses at a 2-week interval and challenged with PRRSV at 7 weeks postinitial immunization. A vaccination-dependent gradational increase in the elicitation of serum and saliva anti-PRRSV IgG and IgA was observed. Furthermore, significantly lower viraemia and tissue viral load were recorded when compared with the pigs fed with untransformed banana leaves. The results suggest that transgenic banana leaves expressing recombinant GP5 protein can be an effective strategy for oral delivery of recombinant subunit vaccines in pigs and can open new avenues for the production of vaccines against PRRSV.

 

Ed Rybicki‘s insight:

Yah.  Um.  Well.  OK, the study actually showed results indicating that feeding piglets with transgenic banana leaf material containing PRRSV GP5 protein is an effective strategy to prevent disease after viral challenge, and to significantly decrease viral load.  Even if the expression levels were very low, and the amount of antigen per feed was of the order of 10 ug/dose – which, for a piglet, is VERY low for an oral dose!  So – a qualified success, then, which could doubtless be improved upon in terms of expression and dose and response.

But it’s back to the days of "a banana a day, keeps the vaccinator away".

Which, although it is a noble sentiment, simply is not practical for the reasons advanced – which have to do with the fact that bananas can be cultivated near where pigs are raised, and it is easy to include fresh leaves in food.

All of which ignores the fact that vaccines have to (a) be given in controlled doses, (b) the fresh material containing the doses has to be assayed to determine what the dose is.  All of which is a little difficult for a pig famer in a developing country, I would surmise.

All in all, however, the authors have shown that their vaccine is protective, and the concept has promise.  But just maybe they should look at using formulated extracts as a food additive, with a higher-yielding expression system.

See on onlinelibrary.wiley.com