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[SANET-MG] Maize 59122 genetically modified for rootworm protection and herbicide tolerance,
ISIS Press Release 19/04/07
GM Maize 59122 Not Safe
Dismissing differences detected between GM and non-GM feed in safety
tests appears to be common practice, and is condoned by regulatory
authorities. Prof. Joe Cummins and Dr. Mae-Wan Ho
This report has been submitted to the European Food Safety Authority
public consultation on behalf of ISIS. Please circulate widely.
Double-whammy GM maize gets positive opinion from European Food Safety
Maize 59122 is genetically modified for rootworm protection and
herbicide tolerance, and has been developed by Dow Chemical and its
associated company Pioneer Hybrid Seed Company. The variety is based on
the gene transformation event DAS-59122-7, expressing unique binary
proteins Cry34Ab1 and Cry35Ab1 derived from the soil bacterium Bacillus
thuringiensis (Bt) Herculex. DAS-59122-7, and the PAT protein conferring
resistance to the herbicide glufosinate ammonia. The transgenes, along
with control elements including promoters and terminators, are inserted
at a single locus in a maize chromosome . The company has applied to
place Maize 59122 on the market in Europe for use as food, feed,
processing, and other products, and the European Food Safety Authority
(EFSA) has put out its opinion  for public comment. Unsurprisingly,
the EFSA considers maize 59122 ?unlikely to have any adverse effect on
human and animal health or on the environment in the context of its
Simultaneously the company has applied to Canada, China, Japan and Korea
for import and environmental release, and to Mexico, Taiwan and
Australia/New Zealand for food use.
Dow Agrisciences/Pioneer Hybrid International had submitted an
application for non-regulated status for the same transgenic maize to
the United States Department of Agriculture Animal and Plant Health
Inspection Service (USDA/APHIS) in December 2003 , and the transgenic
maize is currently marketed in the US as Herculex RW.
The application to Europe indicated that event 59122, created by
Agrobaterium-mediated transformation, had incorporated synthetic
approximations of three genes: Cry34Ab1 with a maize ubiquitin promoter
and intron and a terminator sequence from potato protease inhibitor II;
Cry35Ab1 with a wheat peroxidise promoter and terminator from potato
protease inhibitor II; and PAT for glufosinate tolerance with 35S CaMV
promoter and terminator. The application also claimed that the genes
were stably inserted at a single locus and there was no evidence of
instability. The application also stated that the transgenes were
incorporated correctly between the left and right borders of T-DNA, and
that 59122 maize does not contain fragments from the vector backbone
. However, the claim to stability appears to depend on a Southern
blot analysis within a single plant breeding generation.
The application claims a ?very broad body of evidence? for the safety of
the transgenic proteins in food and feed. So let?s look at the evidence.
Safety assessment based on surrogate proteins fundamentally flawed
The proteins synthesized from the artificial genes were compared with
proteins synthesized in bacteria and seemed identical (but see later).
The main safety and environmental tests were therefore done on proteins
derived from bacteria, and not from the transgenic maize.
USDA/APHIS conducted an environment assessment of maize event 59122 -
its potential impacts on non-target organisms including threatened and
endangered species ? and concluded the environmental effects
insignificant . However, the bulk of the tests were done also with
proteins isolated from bacteria, not from maize 59122. A fuller
comparison of the insecticidal proteins produced in 59122 with those in
the bacteria used in safety testing revealed that four amino acids in
the C-terminal domain were different in Cry35Ab1. But these differences
were considered negligible .
In general, the C-terminal domain of Bt toxins is involved in structural
stability, ion channel gating, binding to membrane vesicles and
determining insecticidal specificity . A study of Cry34/Cry35
insecticidal proteins from diverse Bt strains showed that Cry 35Ab1
contains a segment similar to the to a beta-trefoil domain that may be a
binding motif for galactose . Some examples of trefoil domains
include those in the toxins from Clostridium botulinum, abrin and ricin
. It seems very cavalier of the USDA to ignore amino acid sequences
in a domain known to be active in important functions, and the EFSA is
Transgenic maize not substantially equivalent to non-transgenic variety
Maize 59122 was analysed and compared with near-isogenic non-GM maize
lines to determine whether or not 59211 was substantially equivalent to
unmodified maize. The maize lines were compared for fibre and minerals,
for amino acids, fatty acids, vitamins, secondary metabolites and
anti-nutrients. One parameter, carbohydrate, was significantly lower in
59122 treated with glufosinate; and 13 of 65 (20 percent) determinants,
including forage fibre, grain amino acids and vitamins, were outside the
levels for conventional maize. The expected level for differences solely
due to chance is just over 3 out of 65 (5 percent). In spite of these
many differences, 59122 was deemed substantially equivalent to
unmodified maize .
Feeding studies inadequate
A sub-chronic study was carried out for 90 days on rats fed 59122 grain
compared with grain from a near isogenic line. For the most part the
differences between animals fed 59122 maize and non-GM maze were not
significant. Nevertheless, significant differences were detected in the
levels of mean corpuscular haemoglobin, haemoglobin concentration, red
cell width, reticulocyte count and platelet count; but these blood
values were ignored . Chickens were fed grain either from 59122 or
from a near-isogenic maize. Carcass and organ weights were measured
after 42 days. For the most part, carcass and organ sizes were not
different, though the livers of female chickens fed transgenic maize
were significantly enlarged, but that, too, was ignored .
Significant differences ignored and regulators turn a blind eye
It has now become customary for company researchers to pass over
significant differences due to the consumption of GM feed in animal
testing, and for regulators to condone such fraudulent practices, as is
clear in the recent re-analysis of Monsanto?s MON 863 feeding study by
independent scientists  (GM Maize MON 863 Toxic, SiS 34). The
significant differences between 59122 and near isogenic maize lines,
detected even when only relatively crude parameters were measured,
obviously cry out for fuller independent studies, and highlight the
inadequacy of current regulatory regimes  (GM Food Nightmare
Unfolding in the Regulatory Sham, ISIS scientific publication, also SiS
The use of proteins produced in bacteria as surrogates for transgenic
proteins in toxicity and other safety tests is not acceptable. In
addition to a thorough characterization of the transgenic proteins and
its mechanism of action in insects and mammals, there must also be long
term feeding trials with the transgenic maize similar to those carried
out for drugs and pesticides . A full safety evaluation should
further include characterizations using micro-array technology, now
available for maize , which would be a great improvement on the kind
of equivocal results used for the claim that 59122 is ?substantially
equivalent? to non-GM maize and hence ?safe?.
In conclusion, maize 59122 has not passed its safety test, and should
not be given market approval.
The Dow Chemical Company Product Safety Assessment Herculex RW Rootworm
Open Consultations Europa ?Food Safety,
Hunst P and Rood T..Application for the Determination of Nonregulated
Status for Bt Cry34/35 Ab1 insect resistant Glufosinate-Tolerant Corn:
Corn Line 59122 2004, http://www.aphis.usda.gov/brs/aphisdocs/03_35301p.pdf
Smith C. Environment Assessment for Dow/Pioneer Rootworm Resistant Corn
Gao Y, Schafer BW, Collins RA, Herman RA, Xu X, Gilbert JR, Ni W,Langer
V and Tagliani LA. Characterization of Cry34Ab1 and Cry35Ab1
insecticidal crystal proteins expressed in transgenic corn plants and
Pseudomonas fluorescens. J Agric Food Chem. 2004, 52(26), 8057-65.
Saraswathy,N and Kumar,P. Protein engineering of delta endotoxins of
Bacillus thuringiensis Electronic Journal of Biotechnology Microbial
Biotechnology 2004, 2,1-12.
Schnepf HE, Lee S, Dojillo J, Burmeister P, Fencil K, Morera L, Nygaard
L, Narva KE and Wolt JD. Characterization of Cry34/Cry35 binary
insecticidal proteins from diverse Bacillus thuringiensis strain
collections. Appl Environ Microbiol. 2005, 71(4),1765-74.
Mancheno JM, Tateno H, Goldstein IJ, Martinez-Ripoll M and Hermoso JA.
Structural analysis of the Laetiporus sulphureus hemolytic pore-forming
lectin in complex with sugars. J Biol Chem. 2005, 280(17),17251-94.
Herman RA, Storer NP, Phillips AM, Prochaska LM and Windels P.
Compositional assessment of event DAS-59122-7 maize using substantial
equivalence. Regul Toxicol Pharmacol. 2007, 47(1),37-47.
Malley LA, Everds NE, Reynolds J, Mann PC, Lamb I, Hood T, Schmidt J,
Layton RJ, Prochaska LM, Hinds M, Locke M, Chui CF, Claussen F, Mattsson
JL and Delaney B. Subchronic feeding study of DAS-59122-7 maize grain in
Sprague-Dawley rats. Food Chem Toxicol. 2007 In press
McNaughtona J, Robertsa M, Riceb D, Smith B, Hindsb M, Schmidtb J,
Lockec M, Bryant A, Rood.T, Laytonb R, Lamb I and Delaneyb B. Feeding
performance in broiler chickens fed diets containing DAS-59122-7 maize
grain compared to diets containing non-transgenic maizegrain Animal Feed
Science and Technology 2007,132, 227-239.
Ho MW, Cummins J and Saunders PT. GM food nightmare unfolding in the
regulatory sham. Microbial Ecology in Health and Disease 2007 (in
press); also Ho MW. GM food nightmare unfolding and the regulatory sham.
Science in Society 33, 32-35, 2007.
Ho MW. GM maize MON 863 toxic. Science in Society 34 (in press).
Shi C, Thümmler F, Melchinger A, Wenzel G and Lübberstedt.T. Comparison
of transcript profiles between near-isogenic maize lines in association
with SCMV resistance based on unigene-microarrays. Plant Science 2006,
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