Genetic Engineering and
Omitted Health Research: Still No Answers to Ageing Questions
by Terje Traavik and Jack Heinemann
Some of the most crucial scientific
questions concerning the health effects of genetic engineering (GE)
and genetically engineered organisms (GEOs) were raised up to twenty
years ago . Most of them have still not been answered at all, or
have found unsatisfactory answers. We believe, as Mayer and Stirling
 said, “in the end it is often the case that those who choose
the questions determine the answers”. Will another twenty years
pass before societies realize the urgent need for public funding of
genuinely independent risk- and hazard-related research? The time for
such investment is now, so that a new scientific culture with working
hypotheses rooted in the Precautionary Principle (PP)  can discover
other, possibly even more important questions of safety.
In the present paper we will mainly
confine ourselves to putative health hazards related to GE plants (GEPs)
used as food or feed, with some brief notes on GE vaccines as well as
the novel RNAi- and nanobio-technologies. Our focus is not because we
do not recognize the paramount, indirect threats to public health posed
by social, cultural, ethical and economic issues, as well as the complexities
posed by the relevant legal and regulatory environments, but for reasons
In the specific context of food
or feed safety assessment, ”hazard” may be defined as a
biological, chemical or physical agent in, or condition of, food with
the potential to cause an adverse health effect. The hypothetical hazards
of whole GM foods, i.e. those hazards that have been realized so far,
fall into a few broad categories.
First, there are those either related
to the random and inaccurate integration of transgenes into recipient
plant genomes, uncertainty with regard to direct or indirect effects
of the polypeptide product of the transgene, or uncertainty with regard
to DNA types and circumstances promoting uptake and organ establishment
of foreign DNA from mammalian gastro-intestinal tracts . The second
are those that might come from the purposeful production of potential
hazards such as allergens or powerful pharmaceutical products.
A number of scientific concerns
have been raised in connection with public and animal health. In the
following sections we will discuss, in some detail, a few of these.
Some of them have been thoroughly discussed in excellent, very recent
Our contribution is based on “gene
ecology”; a new, cross-disciplinary scientific field intended
to provide holistic knowledge based on the Precautionary Principle .
Some of the concerns we raise will
also be relevant for environmental risk assessments of GEOs due to the
fact that the processes discussed can take place in an ecosystem at
large as well as in the ecosystems at the scale of the human being.
Do we know that any GE food/feed
is safe for consumption?
For a composite material like food/feed,
reductionist approaches testing single components in vitro are highly
unsatisfactory and cannot clarify important safety issues. In spite
of the obvious need, very few studies designed to investigate putative
effects of GE nucleic acids or food/feed on potential animal or human
consumers have been published in peer-reviewed journals . A consensus
has emerged that the effects observed in some published studies 
must be experimentally followed up. To this day, this has not been done.
Most of the animal feeding studies
conducted so far have been designed exclusively to reveal husbandry
production differences between GEOs and their unmodified counterparts.
Studies designed to reveal physiological or pathological effects are
extremely few, and they demonstrate a quite worrisome trend : Studies
performed by the industry find no problems, while studies from independent
research groups often reveal effects that should have merited immediate
follow-up, confirmation and extension. Such follow-up studies have not
been performed. There are two main factors accounting for this situation:
The lack of funds for independent research, and the reluctance of producers
to deliver GE materials for analysis .
Can we rely on the transgenic
DNA sequences given by GE food/feed producers?
If the transgenic DNA sequences
given in the notifications differ from the inserted sequences found
in the GEPs, the risk assessments made prior to approval of the GEPs
for marketing do not necessarily cover the potential risks associated
with the GEPs.
The most thoroughly studied transgenic
Bt-transgenic maize Mon810
Bt- and glufosinate-transgenic maize Bt176
Glyphosate-transgenic maize GA21
Glufosinate-transgenic maize T25 (Liberty Link)
Glyphosate-transgenic soybean GTS 40-3-2
Even amongst the most thoroughly
studied and some of the oldest commercial GEPs, recent independent work
has revealed that rearrangements occur in transgene inserts and the
nature of the rearrangements varies. Deletions (Mon810, GA21, Bt176),
recombination (T25, GTS 40-3-2, Bt176), tandem or inverted repeats (T25,
GA21, Bt176) as well as rearranged transgenic fragments scattered through
the genome (Mon810) have been reported .
The transgenic modification techniques
are prone to introduce such rearrangements because exogenous DNA transfer
in plants elicits a “wound” response, which activates nucleases
and DNA repair enzymes. This may result in either degradation of the
incoming DNA, or insertion of rearranged copies into the plant DNA .
In addition, the nature of the DNA constructs used to make transgenic
plants may influence the rearrangement tendencies for a given transgenic
event. Some genetic elements in the constructs may act as “hotspots”
and elicit recombination at high frequencies .
While it was earlier assumed that
integration of transgenic constructs took place at random locations
in the recipient plant genome, it has now become apparent that integration
sites are often concentrated in or near elements such as retrotransposons
(T25, Mon810, GA21) and repeated sequences (Bt11 maize) , and this
poses additional risks. Firstly, by introducing a new promoter or new
enhancer motifs, transgenic insertions into, or close to, such elements
may lead to altered spatial and temporal expression patterns of plant
genes located close to and even far from, the insert. Secondly, a strong
retrotransposon LTR promoter may upregulate the transgene expression
level. Thirdly, defective retrotransposons may start “jumping”
under the influence of transacting factors recruited by the insert .
All these events may have unpredictable effects on the long-term genetic
stability of the GEOs, as well as on their nutritional value, allergenicity
and toxicant contents. These! putative processes represent areas of
omitted research with regard to health effects of GEOs.
Are transgenic DNA and proteins
taken up from the mammalian GIT (gastro-intestinal tract)?
If DNA and proteins from GEOs persist
in, and are taken up from the mammalian GIT, this could theoretically,
as will be further explained below, ultimately lead to development of
chronic disease conditions. The fate and consequences of DNA persistence
and uptake is, however, not extensively studied, and therefore represents
yet another area of uncertainty connected to GEPs.
It has generally been claimed that
DNA and proteins are effectively degraded in mammalian GITs. This has
been based on assumptions that have never been systematically examined
. A restricted number of recent publications have demonstrated that
foreign DNA and also proteins may escape degradation, to persist in
the GIT and even to be taken up from the intestines and transported
by the blood to internal organs in biologically meaningful versions
. These findings should not have come as such a surprise, since
scientific articles from the 1990s  strongly indicated that this
was an area of omitted research, as stated by a number of reports .
Briefly summarised, there is evidence
that relatively long fragments of DNA survive for extended periods after
ingestion. DNA may be detected in the faeces, the intestinal wall, peripheral
white blood cells, liver, spleen and kidney, and the foreign DNA may
be found integrated in the recipient genome. When pregnant animals are
fed foreign DNA, fragments may be traced to small cell clusters in foetuses
and newborns. The state of GIT filling, and the feed composition may
influence DNA persistence and uptake. Complexing of DNA with proteins
or other macromolecules may protect against degradation.
So far only two published reports
have investigated the fate of foreign/transgenic DNA in humans .
The consequences of DNA persistence and uptake thus represent yet another
area of omitted research. Extrapolating from a number of experiments
in mammalian cell cultures and in experimental animals, it is conceivable
that in some instances insertion of foreign DNA may lead to alterations
in the methylation and transcription patterns of the recipient cell
genome, resulting in unpredictable levels of gene expression levels
and products. Furthermore, even small inserts may result in a so-called
“destabilisation” process, the end-point of which may be
malignant cancer cells .
The BSE/new variant Creutzfeld-Jacob’s
Disease epidemics caused by prion proteins painfully illustrated the
phenomenon of protein persistence, uptake and biological effects. Two
recent publications indicate that this phenomenon may be more general
that realized . A hallmark of prion diseases and a number of other
debilitating, degenerative diseases, e.g. Alzheimer’s and Huntington’s
diseases, is deposition of “amyloid fibrils”. Recent studies
indicate that any protein can adopt a confirmation known as “amyloid”
 upon exposure to appropriate environmental conditions. Whether
those conditions are more likely when proteins are expressed in different
species and at very different concentrations, as is often the case for
GE food/feed that are already in the marketplace, is unknown.
The consequences of protein persistence
and uptake will vary with the given situation. Generally speaking, there
is a possibility that toxic, immunogenic/allergenic or carcinogenic
molecules may gain entry to the organism via cells in the gastrointestinal
walls. The persistence of the Bt-toxin Cry1Ab in faeces means a potential
for spread on the fields through manure. The ecological effects, e.g.
on insect larvae and earthworms , are at the moment an issue of
Have the protein contents
of GE food been altered in unpredictable ways?
Transgenes or upregulated plant
genes may give rise to toxicants, anti-nutrients, allergens and, putatively,
also carcinogenic or co-carcinogenic substances. The concentration of
a given transgenic protein may vary according to the location(s) in
the recipient host cell genome of inserted GE construct DNA, and to
environmental factors influencing the activity of the transgenic regulatory
elements, e.g. the 35S CaMV promoter. The biological effects of a given
transgenic protein, e.g. the Cry1Ab Bt-toxin or the ?-amylase inhibitor
from beans when expressed in peas , may be unpredictably influenced
by post-translational modifications, alternative splicing , alternative
start codons for transcription, chimeric reading frames resulting from
integration into the reading frame of a plant gene, and complex formation
with endogenous plant proteins.
The influence of foreign DNA insertion
on endogenous plant gene expression patterns may vary with local environmental
factors, the actual insertion site(s), the number and stability of the
inserts, transgenic promoter effects, methylation patterns of the insert(s),
and post-transformational mutations in the transgenic protein coding
as well as in regulatory sequences. Even a single nucleotide change
may affect the properties of a protein, or it may create a new transcription
factor-binding motif. Detailed studies of these phenomena under authentic
conditions are lacking, and hence we are confronted with yet another
area of omitted research.
Could GE food/feed cause
One of the major health concerns
related to GEPs is that the transgenic product itself, e.g. a Bt toxin,
changed expression of endogenous plant genes, or chemical reactions
that occur during the cooking of novel foods, may result in exposure
to allergenic compounds. The risk assessment of allergens often follows
an allergenicity decision tree . These “trees” are based
on in vitro tests comparing a limited number of structures, usually
only one, of the transgenic protein with known allergens. Hence, these
comparisons are hopeful that the protein isolated for the test matches
all proteins produced from the same gene in the GEP. But in fact, this
is unlikely because allergenicity tests are usually carried out with
bacteria-, not in planta-produced versions of the transgenic protein.
Glycosylation invariably takes place in plants, but not in bacteria,
so this form of post-translational modification of both the transgenic
protein and endogenous proteins would not be tested. A! llergenic characteristics
of proteins, and also their resistance to degradation in the organism,
can be affected by glycosylation. Other protein modifications may also
take place, adding to the unpredictability of transgenic products .
Another important question related
to allergenicity is whether post marketing surveillance can provide
useful information about allergens in GE foods. For a number of reasons
this is not likely to happen . Treatment of allergy is symptomatic,
whatever the cause may be. The allergic case is often isolated, and
the potential allergen is rarely identified. The number of allergy-related
medical visits is not tabulated. Even repeated visits due to well-known
allergens are not counted as part of any established surveillance system.
Thus, during the October 2000 Starlink episode, it proved very difficult
to evaluate Starlink (containing Bt-toxin Cry9C) as a human allergen
. An additional reason for this was that the ELISA tests, used by
FDA, that found no anti-Cry9C antibodies in suspected human cases, were
dubious because bacterial, recombinant antigens were used instead of
the Cry9C maize versions that the individuals had been exposed to.
Case: Bt toxins in Bt-transgenic
It is very important to be aware
of the fact that the Bt-toxins expressed in GEPs have never been carefully
analysed, and accordingly, their characteristics and properties are
not known. What is clear from the starting point, however, is that they
are vastly different from the bacterial Bacillus thuringiensis protoxins,
used in organic and traditional farming and forestry for decennia .
The difference is evident already at the gene level, since the versions
found in GEOs are engineered to produce active Bt toxins. By extrapolation,
these have a number of potentially unwanted biological characteristics,
ranging from solubilization of the protein under natural conditions
and effects on insect and mammalian cells, to persistence and non-target
effects in the environment . In addition, the post-translational
modifications that may influence conformations, cellular targets and
biological effects of GEP-expressed Bt-toxins are unknown, and hence
we once more identify an ar! ea of omitted research.
During the last few years a number
of observations that may be conceived of as “early warnings”
of potential health and environmental risks, have appeared in the literature
. Most of them have, however, not been followed up by extended studies.
Case: Transgenic, glyphosate-tolerant
(Roundup Ready) GEPs
Glyphosate kills plants by inhibiting
the enzyme 5-enolpyruvoyl-shikimate-3-phosphate synthase (EPSPS), necessary
for production of important amino acids. Some microorganisms have a
version of EPSPS that is resistant to glyphosate inhibition. The transgene,
cp4 epsps, used in genetically modified crops was isolated from an Agrobacterium
strain. The whole idea is of course the combined use of the GEP and
the herbicide. Recent studies indicate that in some cases such GEPs
are associated with greater usage of glyphosate than the conventional
counterparts . A very restricted number of experimental studies
have been devoted to health or environmental effects of the GEPs or
the herbicide itself. Some of these may be considered “early warnings”
of potential health and environmental risks, and they should be rapidly
followed up to confirm and extend the findings . Consequently: yet
another area of omitted research.
Is the 35S CaMV promoter
inactive in mammalian cells?
Cauliflower mosaic virus (CaMV)
is a DNA-containing para-retrovirus replicating by means of reverse
transcription (Poogin et al., 2001). One of the viral promoters, called
35S, is a general, strong plant promoter. It has been used to secure
expression of the transgenes in most of the GEOs commercialized so far.
Industry proponents have claimed
unconditionally that the 35S is an exclusive plant promoter, and hence
cannot, even theoretically, represent a food/feed safety issue .
In addition to studies in yeast
 and in Schizosaccharomyces pombe , there are published studies
indicating that the 35S CaMV promoter might have potential for transcriptional
activation in mammalian systems . And the final proof has become
available during the last couple of years. First, 35S promoter activity
was demonstrated in human fibroblast cell cultures , thereafter
in hamster cells , and very recently one of us (TT) has demonstrated
substantial 35S promoter activity in human enterocyte-like cell cultures
. Such cells line the surface of human intestines. However, no published
studies have investigated 35S CaMV activity in vivo, and this is hence
an obvious area of omitted research.
Could the use of antibiotic
resistance marker genes (e.g. nptII) present health hazards?
The antibiotic kanamycin is used
extensively in crop genetic engineering as a selectable marker, inter
alia in GE oilseed rape event lines like MS1Bn x RF1Bn and Topas 19/2.
A selectable marker is a gene inserted
into a cell or organism to allow the modified form to be selectively
amplified while unmodified organisms are eliminated. In crop genetic
engineering, the selectable marker is used in the laboratory to identify
cells or embryos that carry the genetic modifications that the engineer
wishes to commercialize. The selection gene is used once briefly in
the laboratory, but thereafter the genetically modified crop has the
unused marker gene in each and every one of its cells.
There are multiple well-known mechanisms
for cross-resistance to antibiotics of a particular type . Kanamycin
is a member of the family aminoglycoside antibiotics. There are approximately
17 different classes of aminoglycoside-modifying enzymes. Some of these
inactivate up to four different aminoglycosides. Cross-resistance between
kanamycin and other aminoglycosides, e.g. gentamycin and tobramycin,
was found to vary markedly between isolates . All of the antibiotics
mentioned are used to treat human diseases.
In spite of the belief of many genetic
engineers that kanamycin is no longer employed in medical applications,
there is evidence that the antibiotic is used extensively for some applications
Concluding remarks: Where
do we go from here?
We have discussed in some detail
a handful of selected, unanswered risk questions related to the first
generation of transgenic GEOs. There are many more risk issues. Among
them are issues of Horizontal Gene Transfer (HGT) , the new generations
of multitransgenic GEOs for pharmaceutical and industrial purposes ,
safety questions related to GE vaccines , the new nanobiotechnology
approaches  and the applications of small double-stranded (ds)RNAs
(which can cause RNAi) for a number of medical purposes . Furthermore,
we have the “questions not yet asked”, and we have the problem
of whether available methods and regulatory frameworks will be able
to pick up and manage the conceived risks once they become reality.
In recent publications it has been
demonstrated that the presently used sampling and detection methods
may fail to detect GE materials in food and feed . In another article
it was demonstrated that HGT events, that potentially carry very serious
public health consequences, would not be detected in time for any meaningful
preventive actions . And it has been illustrated that the dsRNA
techniques are not as “surgically targeted” as initially
We are therefore left with a high
number of risk issues lacking answers, adding up to a vast area of omitted
research, and this falls together in time with a strong tendency towards
corporate take-over of publicly funded research institutions and scientists
We must as citizens and professionals
join together to reverse the present situation. Publicly funded, independent
research grants need to become a hot political issue. That would be
the most efficient remedy for chronically unanswered questions and the
corporate take-over of science. In conclusion, we once more quote Mayer
and Stirling : “Deciding on the questions to be asked and
the comparisons to be made has to be an inclusive process and not the
provenance of experts alone”. But then again, whom should society
rely on for answers and advice should the time come when all science
resource persons work directly or indirectly for the GE producers?
About this paper and its
Many crucial scientific questions
concerning the health effects of genetic engineering and genetically
engineered organisms remain. In this paper, the authors identify some
of the putative health hazards related to genetically engineered plants
used as food or feed. They also identify numerous areas of omitted research,
which need urgent investigation. Their contribution is based on “gene
ecology”; a new, trans-disciplinary scientific field intended
to provide holistic knowledge based on the Precautionary Principle.
Dr. Terje Traavik is the author
of more than 180 scientific articles and book chapters. He was the professor
of virology at the University of Tromsö, Norway from 1983-2003.
Originally a medical and molecular virologist, Traavik later crossed
into molecular and cellular cancer research. In 1992 he received the
Erna and Olav Aakre Foundation Prize for Excellent Cancer Research.
In the early 1990s he was the Board Chairman of the national research
program “Environmental effects of biotechnology”, which
was funded by the Research Council of Norway. In 1997, he initiated
and became the Scientific Director of GENOK-Norwegian Institute of Gene
Ecology, and since 2003 he is also professor of gene ecology at the
University of Tromsö.
Dr. Jack Heinemann is at present
an Assoc. Professor at the School of Biological Sciences, University
of Canterbury, Christchurch. He is the Director of INBI-Centre for Integrated
Research in Biosafety, New Zealand, and an adjunct professor at GENOK-Norwegian
Institute of Gene Ecology. He is listed on the UN Roster of Biosafety
Experts for the Cartagena Protocol on Biosafety. Dr. Heinemann was the
2002 recipient of the New Zealand Association of Scientists Research
Medal. He has published extensively in the literature of horizontal
gene transfer and biosafety as well as related fields within bacterial
genetics and molecular biology.
 See for instance: Freese, W.
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 Mayer, S. and Stirling, A. (2004). GM crops: good or bad? EMBO Reports
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 For a recent, authoritative review: see The Royal Society of Canada
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of allergy to genetically modified foods. Environ Health Perspect 111:
 Schubert, D. (2002). A different perspective on GM food. Nat Biotechnol
20: 969; Submissions on A549 High Lysine Corn LY038 http://www.inbi.canterbury.ac.nz/ly038.shtml
 Bernstein et al. (2003). Clinical and laboratory investigation
of allergy to genetically modified foods. Environ Health Perspect 111:
 Bucchini, L. and Goldman, L.R. (2002). Starlink corn: a risk analysis.
Environ Health Perspect 110: 5-13.
 Stotzky, G. (2002). Release, persistence, and biological activity
in soil of insecticidal proteins from Bacillus thuringiensis. Pp. 187-222
in: Deborah K. Letourneau and Beth E. Burrows: Genetically Engineered
Organisms. Assessing Environmental and Human Health Effects. CRC Press
LLC (ISBN 0-8493-0439-3).
 Andow, D.A. (2002). Resisting resistance to Bt-corn. Pp. 99-124
in: Deborah K. Letourneau and Beth E. Burrows: Genetically Engineered
Organisms. Assessing Environmental and Human Health Effects. CRC Press
LLC (ISBN 0-8493-0439-3).
 Human and monkey cells exposed to Bt-toxins from the extra- or
intra-cellular environment are killed or functionally disabled (Taybali
and Seligy (2000). Human cell exposure assays of Bacillus thuringiensis
commercial insecticides: Production of Bacillus cereus-like cytolytic
effects from outgrowth of spores. Environ Health Perspect online, 18
August 2000; Tsuda et al. (2003). Cytotoxic activity of Bacillus thuringiensis
Cry proteins on mammalian cells transferred with cadherine-like Cry
receptor gene of Bombyx mori (silkworm). Biochem J 369: 697-703; Namba
et al. (2003). The cytotoxicity of Bacillus thuringiensis subsp. coreanensis
A 1519 strain against the human leukemic T cell. Biochimica et Biophysica
Acta 1622: 29-35). Influenza A infections in mice were changed from
silent to lethal encounters by co-exposing the animals to Bt-toxin (Hernandez
et al. (2000). Super-infection by Bacillus thuringiensis H34 or 3a3b
can lead to death in mice infected with the influenza! A virus. FEMS
Immunology and Med Microbiol 209: 177-181). Farmworkers exposed to Bt
spores developed IgG and IgE antibodies to Bt-toxin (Cry1Ab) (Taylor
et al. (2001). Will genetically modified foods be allergenic? Journal
of Allergy and Clinical Immunology, May 2001, 765-771). The Bt-toxin
Cry1Ac was found to have very strong direct and indirect immunological
effects in rodents (Vazquez et al. (2000). Characterization of the mucosal
and systemic immune response induced by Cry1Ac protein from Bacillus
thuringiensis HD 73 in mice. Brazilian Journal of Medical and Biological
Research 33: 147-155; Moreno-Fierros et al. (2000). Intranasal, rectal
and intraperitoneal immunization with protoxin Cry1Ac from Bacillus
thuringiensis induces compartmentalized serum, intestinal, vaginal and
pulmonary immune response in Balb/c mice. Microbes and Infection 2:
885-890; Moreno-Fierros et al. (2002). Slight influence of the estrous
cycle stage on the mucosal and systemic specific antibody ! response
induced after vaginal and intraperitoneal immunization with p rotoxin
CryA1c from Bacillus thuringiensis in mice. ELSEVIER Life Sciences 71:
2667-2680). Earthworms exposed to Bt toxin Cry1Ab experience weight
loss (Zwahlen et al. (2003). Effects of transgenic Bt corn litter on
the earthworm Lumbricus terrestris. Molecular Ecology 12: 1077-1086).
Cattle fed the Bt176 maize variety demonstrated undegraded Cry1Ab through
the whole alimentary tract, and the intact toxin was shed in faeces
(Einspanier et al. (2004). Tracing residual recombinant feed molecules
during digestion and rumen bacterial diversity in cattle fed transgene
maize. Eur Food Res Technol 218: 269-273). Cry1Ab is much more resistant
to degradation under field soil conditions than earlier assumed (Zwahlen
et al. (2003). Degradation of the Cry1Ab protein within transgenic Bacillus
thuringiensis corn tissue in the field. Mol Ecol 12: 765-775). Potentially
IgE-binding epitopes have been identified in two Bt-toxins (Kleter and
Peijnenburg (2002). Screening of transgenic protein! s expressed in
transgenic food crops for the presence of short amino acid sequences
identical to potential IgE-binding linear epitopes of allergens. BMC
Structural Biology 2:8), and it should be added that many IgE-binding
epitopes are conformationally not linearly determined. Finally, it is
a matter of concern that Bt-toxins have lectin characteristics (Akao
et al. (2001). Specificity of lectin activity of Bacillus thuringiensis
parasporal inclusion proteins. J Basic Microbiol. 41(1): 3-6). Lectins
are notorious for finding receptors on mammalian cells. This may lead
to internalization and intracellular effects of the toxins. Occupational
exposure to novel proteins, and potential allergic sensitization, has
had little study, but could be of public health significance. An amazing
number of foods have been proven to evoke allergic reactions by inhalation
(Bernstein et al. (2003). Clinical and laboratory investigation of allergy
to genetically modified foods. Genetically Modi! fied Foods, Mini-Monograph,
Volume 111, No. 8, June 2003). In this con nection the findings of serum
IgG/IgE antibodies to B. thuringiensis spore extracts (Bernstein et
al. (1999). Immune responses in farm workers after exposure to Bacillus
thuringiensis pesticides. Environmental Health Perspectives 107(7):
575-582), in exposed farm workers should be given further attention.
Inhalant exposure to Bt-toxin containing GMP materials may take place
through pollen in rural settlements and also through dust in workplaces
where foods are handled or processed.
 Benbrook, C. Impacts of genetically engineered crops on pesticide
use in the United States: The first eight years. Biotech InfoNet Paper
No. 6, November 2003. www.biotech-info.net/technicalpaper6.html
 Mice fed GE soybean demonstrated significant morphological changes
in their liver cells (Malatesta et al. (2002). Ultrastructural morphometrical
and immunocytochemical analysis of hepatocyte nuclei from mice fed on
genetically modified soy bean. Cell Structure and Function 27: 173-180).
The data suggested that epsps-transgenic soybean intake was influencing
liver cell nuclear features in both young and adult mice, but the mechanisms
responsible for the alterations could not be identified by the experimental
design of these studies. Treatment with glyphosate (Roundup) is an integrated
part of the epsps-transgenic GMP application. A number of recent publications
indicate unwanted effects of glyphosate on aquatic (Solomon and Thompson
(2003). Ecological risk assessment for aquatic organisms from over-water
uses of glyphosate. J Toxicol Environ Health B Crit Rev. 6(3): 289-324)
and terrestric (Ono et al. (2002). Inhibition of Paracoccidioides brasiliensis
by pesticides: is ! this a partial explanation for the difficulty in
isolating this fungus from the soil? Med Mycol 40(5): 493-9; Blackburn
and Boutin (2003). Subtle effects of herbicide use in the context of
genetically modified crops: A case study with glyphosate (Roundup).
Ecotoxicol 12: 271-285) organisms and ecosystems. Recent studies in
animals and cell cultures point directly to health effects in humans
as well as rodents and fish. Female rats fed glyphosate during pregnancy
demonstrated increased foetal mortality and malformations of the skeleton
(Dallegrave et al. (2003). The teracogenic potential of the herbicide
glyphosate Roundup in Wistar rats. Toxicology letters 142: 45-52). Nile
Tilapia (Oreochromis niloticus) fed sublethal concentrations of Roundup
exhibited a number of histopathological changes in various organs (Jiraungkoorskul
et al. (2003). Biochemical and histopathological effects of glyphosate
herbicide on Nile tilapia. Environ Toxicol 18(4): 260-7). A study of
Roundup ef! fects on the first cell divisions of sea urchins (Marc et
al. (2002). Pesticide Roundup provokes cell division dysfunction at
the level of CDK1/Cyklin B activation. Chem Res Toxicol 15: 326-331)
is of particular interest to human health. The experiments demonstrated
cell division dysfunctions at the level of CDK1/Cyclin B activation.
Considering the universality among species of the CDK1/Cyclin B cell
regulator, these results question the safety of glyphosate and Roundup
on human health. In another study (Axelrod et al. (2003). The effect
of acute pesticide exposure on neuroblastoma cells chronically exposed
to diazinon. Toxicoloy 185: 67-78) it was demonstrated a negative effect
of glyphosate, as well as a number of other organophosphate pesticides,
on nerve-cell differentiation. Surprisingly, in human placental cells,
Roundup is always more toxic than its active ingredient. The effects
of glyphosate and Roundup were tested at lower non-toxic concentrations
on aromatase, the enzyme responsible for estrogen synthesis (Richard,
S. et al. (2005)! . Differential effects of glyphosate and Roundup on
human placental cells, Environ. Health Perspect. 113: 716-720). The
glyphosate-based herbicide disrupts aromatase activity and mRNA levels
and interacts with the active site of the purified enzyme, but the effects
of glyphosate are facilitated by the Roundup formulation. The authors
conclude that endocrine and toxic effects of Roundup, not just glyphosate,
can be observed in mammals. They suggest that the presence of Roundup
adjuvants enhances glyphosate bioavailability and/or bioaccumulation.
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virus 35S RNA leader is a special case of reinitiation of translation
functioning in plant and animal systems. Genes & Development 14:
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of plant promoters and Poly(A) sites in Xenopus oocytes. Nucleic Acids
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circular, supercoiled 35S CaMV driven expression plasmids were more
active than linear forms. The CaMV genome carries structural and functional
resemblance to mammalian Retroviridae and to Hepadnaviridae, which contains
the human hepatitis B virus (HBV). A 19 bp palindromic sequence, including
the TATA box of the 35S CaMV promoter, may act as a recombination hotspot
in plants (Kohli et al. (1999). Molecular characterization of transforming
plasmid rearrangements in transgenic rice reveals a! recombination hotspot
in the CaMV 35S promoter and confirms the predominance of microhomology
mediated recombination. Plant Journal 17(6): 591-601), and it is unknown
whether this is also the case in mammalian cells. In a recent review
article (Ho et al. (2000). Hazardous CaMV? Nat Biotechnol 18(4): 363)
it was hypothesized that the 35S CaMV promoter might represent health
hazards to human and animal consumers of transgenic plant materials.
Against this it was argued that humans and mammals are continuously
being exposed to CaMV particles through infected plant materials. This
is true enough, but it is then forgotten that there are documented examples
of animal species being resistant to intact viruses, but highly susceptible
to infection by DNA from the same virus (Refs: Rekvig et al. (1992).
Antibodies to eukaryotic, including autologous, native DNA are produced
during BK virus infection, but not after immunization with non-infectious
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 Heinemann, J.A., Ankenbauer, R.G., and Amábile-Cuevas, C.F.
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with kanamycin B in inhibiting RNase P ribozyme 16s ribosomal RNA and
tRNA maturation (Mikkelsen et al. (1999). Inhibition of RNase P RNA
cleavage by aminoglycosides. Proc Natl Acad Sci USA 96: 6155-6160).
 Kanamycin is used prior to endoscopy of colon and rectum (Ishikawa
et al. (1999). Prevention of infectious complications subsequent to
endoscopic treatment of the colon and rectum. J Infect Chemother 5:
86-90) and to treat ocular infections (Hehl et al. (1999). Improved
penetration of aminoglycosides and fluorozuinolones into the aqueous
humour of patients by means of Acuvue contact lenses. Eur J Clin Pharmacol.
55(4): 317-23). It is used in blunt trauma emergency treatment (Yelon
et al. (1996). Efficacy of an intraperitoneal antibiotic to reduce the
incidence of infection in the trauma patient: a prospective, randomized
study. J Am Coll Surg 182(6): 509-14), and has been found to be effective
against E coli 0157 without causing release of verotoxin (Ito et al.
(1997). Evaluation of antibiotics used for enterohemorrhagic Escherichia
coli O157 enteritis-effect of various antibiotics on extracellular release
of verotoxin. Kansenshogaku Zasshi 71(2): 130-5).
 Heinemann, J.A. and Billington, C. (2004). How do genomes emerge
from genes? Horizontal gene transfers can lead to critical differences
between species when those genes begin reproducing vertically. ASM News
 Twyman, R.M. et al. (2003). Molecular pharming in plants: host
systems and expression technology. Trends in Biotechnology 21: 570-578.
 Traavik, T. (2002).Environmental risks of genetically engineered
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Organisms: Assessing Environmental and Health Effects. CRC Books, La
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 Mazzola, L. (2003). Commercializing nanotechnology. Nat Biotechnol
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of engineered nanomaterials. Nat Biotechnol 21: 1166-1170.
 Hannon, G.J. and Rossi, J.J. (2004). Unlocking the potential of
the human genome with RNA interference. Nature 431: 371-378.
 Heinemann J.A., Sparrow A.D. and Traavik T. (2004). Is confidence
in the monitoring of GE foods justified? Trend Biotechnol 22: 331-336.
 Heinemann J.A. and Traavik, T. (2004). Problems in monitoring horizontal
gene transfer in field trials of transgenic plants. Nat Biotechnol 22:
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gene transfer. Reply. Nat Biotechnol 22: 1349-1350.
 E.g. Jackson, A.L. et al. (2003). Expression profiling reveals
off-target gene regulation by RNAi. Nat Biotechnol 21: 635-637, and
a number of other recent articles.
 Mayer, S. and Stirling, A. (2004). GM crops: good or bad? EMBO
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