Barbara H. Peterson
For years we have been told that genetically engineered crops (GMOs) are “substantially equivalent” to their non-engineered counterparts. But what does that mean?
The term substantial equivalence was first mentioned in connection with food safety in a report of the OECD Group of National Experts on Safety in Biotechnology (OECD, 1993). The members of the group agreed that the most practical approach to determining the safety of foods derived by modern biotechnology is to consider whether they represent a substantial equivalent to analogous traditional products. The term substantial equivalence and the underlying approach were “borrowed from the US Food and Drug Administration’s (FDA) definition of a class of new medical devices that do not differ materially from their predecessors and thus, do not raise new regulatory concerns” (Miller, 1999).
In other words, not different enough to warrant concern. So, if GMOs are substantially equivalent to their natural counterparts, this means that they are basically the same in every respect, except of course, for that minor detail of having been manufactured in a laboratory, genetically engineered with viruses, bacteria and genes from species that would never combine in the natural world, and are engineered to be resistant to pesticides and/or to kill bugs with one bite. But not to worry, they are substantially equivalent. Or are they?
A Brazilian study has found unintended differences in proteins between a GM maize and the non-GM parent variety
Comparison of the GM and non-GM plants revealed a total of 32 different proteins that were differentially expressed. The proteins were either present, absent, up- or down-regulated in one of the hybrids, at a statistically significant level…
The ‘substantial equivalence theory’ regulatory “method is rather vague and does not specify the level of similarity between the chemical composition of plants that allow them to be considered “equivalent”, but it still secured the release of GMOs in the USA and other countries and is still used today (including by CTNBio – National Technical Biosafety Commission) to justify not carrying out in-depth studies to assess risks of the new plants.
Not so equivalent after all, eh? What would happen if we applied the same reasoning to other living beings that biotech and the US government apply to GMO crops?
An international team of researchers has sequenced the genome of the bonobo for the first time, confirming that it shares the same percentage of its DNA with us as chimps do. The team also found some small but tantalizing differences in the genomes of the three species—differences that may explain how bonobos and chimpanzees don’t look or act like us even though we share about 99% of our DNA.
It appears that we share about 99% of our DNA with the bonobo chimp. The difference is in the way the genes are expressed.
Gene expression differences
According to Oldham et al., a major genome paradigm is now recognized for which
“ … the high extent of sequence homology between human and chimpanzee proteins supports the longstanding hypothesis that many phenotypic differences between the species reflect differences in the regulation of gene expression, in addition to differences in amino acid sequences.”32
In fact, as early as 1975 King and Wilson postulated that the major differences between humans and apes were due largely to factors controlling gene expression:
“We suggest that evolutionary changes in anatomy and way of life are more often based on changes in the mechanisms controlling the expression of genes than on sequence changes in proteins. We therefore propose that regulatory mutations account for the major biological differences between humans and chimpanzees.”33
The only logical conclusion that one can come to when trying to determine the reasoning behind biotech’s “substantial equivalence” doctrine is that gene expression is not a consideration. If gene expression is not a consideration, then there is nothing to separate man from ape, and the CEO of Monsanto is substantially equivalent to our furry friend, the bonobo chimp.
©2014 Barbara H. Peterson