Biotech advocates often give U the impression that trans-species bioengineering is merely a matter of taking a gene from 1 organism & popping it into the DNA of another, where it’s seamlessly received & ready 2 function flawlessly

In reality, many steps r required.

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Before a gene can be utilized, it must be isolated; & isolating a gene is complicated. Gene editors gain the knowledge required by doing extensive analysis – which itself entails a lot of cutting with restriction enzymes. Once isolated, the gene needs to be copied.

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One or two copies aren’t going to cut it either. Vast #s are needed & several steps are required 2 achieve the massive multiplication.

Then they need to be inserted into the target organism. Geneticists use plasmids which are what bacteria use 4 horizontal gene transfer.

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Once a gene is spliced into a plasmid & the plasmid is transferred to the bacterium, that gene can be transcribed into RNA & translated into protein; & because the plasmid will replicate, the gene will continue to appear in successive generations of bacterial cells.

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To prepare the plasmids for the insertion of the genes, they’re cut open with the same restriction enzymes that were used to cut the genes from their surrounding strand of DNA. In this way, the open ends in the plasmids

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will be complementary to the ends of the segment carrying the gene, enabling the ends to fit together. Further, because the complementary ends are “sticky” in relation to one another, the attractive force between the complementary bases facilitates bonding.

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However, the sticky ends are not sticky enough. So biotechnicians have to apply an enzyme (called a ligase) that cells ordinarily use to repair breaks in their own DNA. In this way, a stable bond is formed.

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The next step is to get the plasmids into the E. coli. Since they won’t take up isolated DNA from their surroundings, biotechnicians must resort to artificial manipulation.

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In order to do this they apply electrical shock which opens pores in the cell wall with pulses of high-voltage current. But we’re getting a little ahead of ourselves. Prior to inserting genes into plasmids, the DNA itself must be manipulated.

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Because large numbers of engineered plasmids are going to be mixed with large numbers of bacteria, & because only a small fraction of the bacteria will end up containing one of the plasmids, biotechnicians need some way to identify the ones in that latter group.

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So they add another gene 2 the gene they want 2 transfer, 1 that will produce a distinct/easily observed effect. The genes often employed as markers confer resistance 2 a particular antibiotic. They’ll use the antibiotic to kill off everything else & r left w/their target.

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But wait there’s more. The genes of bacteria r simple. Those genes in plants/animals that bioengineers want 2 incorporate r too sophisticated for bacteria. In bacteria, all genes are expressed into proteins. In plants/animals, there are several sections not producing proteins

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The expressed regions r exons. The non-expressed regions r introns. Geneticists weren’t aware of introns in 1977 & didn’t know why they were there (they do post-transcription editing of protein). In order 2 produce extrons w/o introns, geneticists use reverse transcriptase

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Retroviruses use RNA to transcribe itself into host DNA. RNA transcripts in higher organisms don’t work as well as in viruses so more tinkering. They must add chemical primers to efficiency.

Even with all of this, shedding introns from higher organisms is inexact.

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To make it even more complicated, amino acids are built from parts (codons) & bacteria use some types (exclude others) whilst plants/animals use ones that bacteria shun. So geneticists have to monkey with plant/animal codons so bacteria can read them.

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But wait, there’s more. There are several other elements in plant/animal DNA that helps construct proteins not found in bacteria such as promoters (promotes process of expression). It doesn’t just “promote” expression however.

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It prevents the process from starting when inappropriate, & it shuts the process down when expression of the gene is no longer necessary. However taking this promoter out of plants/animals & into bacteria it will no longer be sensitive to signals.

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So b4 transferring a plant or animal gene 2 a bacterium, biotechnicians have to remove the native promoter & affix one that will function within the foreign surroundings. Often times they want the gene expressed @ unnaturally levels & will use a viral promoter in bacteria.

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But they had 2 replace more than the just the promoter sequence (@ the beginning of the gene sequence), they also needed 2 replace the terminator sequence (@ the end of the gene sequence). Terminators from plants/animals r not recognized by the bacteria transcription enzymes

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Gene engineering requires the transferring of a gene along with its regulatory elements (promoter, terminator, marker) that will enable it to function in the alien organism. These conglomerates are referred 2 as cassettes & hyperactive which is highly problematic.

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These cassettes will generate foreign proteins at a high clip which results in all kinds of deleterious downstream effects. Equating natural cross-breeding between “like species” & gene engineering is laughable.

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As difficult it is to transfer foreign genes 2 bacteria, it’s even worse for trying 2 get them into plants. The task was so arduous that close 2 9 yrs elapsed b/n the appearance of the 1st genetically engineered bacterium & the creation of the 1st functional engineered plant.

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However, instead of using a virus, a bacterium is used. The bacterium’s technical name is Agrobacterium tumefaciens, & the genes it deploys to infect plant cells are part of a large plasmid that it carries.

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When a plant is wounded, these bacterium advance to the injury, surge thru the break in the surface, & form mating tubes that connect with adjacent plant cells. This allows them 2 send large segments of DNA from their plasmids thru the walls of the targeted cells &

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into the nuclei, where the segments are integrated within the native DNA. However, there were still incompatibilities. The codons of a bacterial gene had to be revised so they would mesh with the predilections of plants. Further, the promoters & terminators that adjoined

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the bacterial genes destined for GE foods had to be removed, because they couldn’t coordinate with the plants’ processes either. However, there were some exceptional promoter/terminator sets in the bacterial realm that could function in plants, and they were the ones

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enabling the Ti genes of Agrobacteria to work their mischief. Even though the inserted DNA was now getting expressed, there was still a problem. The Agrobacterium’s promoters didn’t reliably generate the level of protein that was needed in most commercial applications.

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So they too had to be replaced. They found their answer back in the viral realm. This pathogen was named the cauliflower mosaic virus, and, for technical reasons, its muscular gene activator was called the 35S promoter. Not only was this promoter extremely powerful, it was

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Versatile. It could subjugate the transcribing enzymes of almost any plant into which it was inserted. However, there are some species in which even the 35S is insufficiently forceful, biotechnicians had to alter its structure to make it hyper-active so it could adequately

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function within these plants as well. Despite their broad infective range, several plants would not succumb to their transformational powers; and, to the dismay of the bioengineers, among them were the two most valuable crops: corn and soy.

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Trying to get foreign genes into corn/soy was near impossible so a very bizarre technique was employed & finally succeeded. It was referred to as particle bombardment (or bioballistics), & it was implemented by a device called a gene gun.

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Initially, the gun that was employed fired a .22-caliber bullet coated with metallic particles which in turn had been coated with DNA. As the gun evolved, macroscopic bullets were no longer used, & the microscopic particles were propelled by a blast of air.

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These contrived modes of gene transfer are highly imprecise. The fragments of foreign DNA enter the target genome in an essentially random manner; & research indicates that they usually disrupt the DNA of the regions into which they wedge.

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Inserting foreign genes into a host cell has unpredictable consequences. In 1 example, scientists used microarray technology to study how gene expression in human cells was effected by insertion of a single copy of a human gene. They discovered that 5% of the assessed genes

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underwent significant changes in their expression levels. The complexity of insertional effects is compounded by the fact that each cell type of the organism tends to respond differently. When organisms are altered by the insertion of a gene that is foreign instead of native

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as is almost always the case with engineered food crops), the magnitude of the changes could b far greater. The disruptive potential is amplified by the presence of the 35S promoter in each haphazardly placed fragment. Because this viral-derived booster is so powerful, it can

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induce erratic expression of some native genes – or activate biochemical pathways that are ordinarily inactive. Moreover, due to their always-on promoters, the transplanted genes act independently of the host organism’s intricate control system, as do the genes of an invading

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virus, in contrast to the harmonious coordination that exists among the native genes. Consequently, not only is every cell of the organism forced 2 produce substances that have never been in that species, it’s forced 2 produce them in an unregulated manner – which can disrupt

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complex biochemical feedback loops. This unrestrained activity is highly unnatural, and it violates a basic principle of living systems: energy efficiency. the viral promoters push organisms off the path of frugality and force them to expend considerable energy to produce

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substances they do not need. This incessant energy drain may b the reason that GE crops sometimes underproduce. Another problem with GE crops Because transferring DNA to a cell by infecting it with Agrobacteria or blasting it with a gene gun does not produce a fertile seed

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as does the union of gametes), biotechnicians cannot grow it into a mature plant by putting it directly into the soil. Instead, they must first develop it with an artificial process called tissue culture, in which it is coaxed to mature via applications of hormones &

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antibiotics in ways that would not naturally occur. Further, whatever the species, tissue culture imparts a broad jolt known as “genomic shock.” 53 This shock induces extensive genetic perturbations – and is another way in which unintended harmful substances can be formed.

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Plants have built-in defense mechanisms & often fight back which can result in transgene inactivation. Thus, not only do GE plants get created through multiple breaches of nature’s boundaries, the foreign genes within them can only continue to function by escaping the plant’s

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natural defenses. Consequently, due to their unnaturalness, and to the disruptions caused by their creation, few GE plants thrive; and a sizable percentage don’t even survive. Besides being numerous, the unintended outcomes of genetic engineering are frequently surprising,

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often bizarre. Like when pigs were implanted with human genes & were born without vaginas or anuses. Or they were 2 lethargic 2 stand up. Additional afflictions included arthritis, enlarged hearts, ulcers, dermatitis, kidney disease, and impaired vision.

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Plants have proven as unpredictable as animals. For instance, when tobacco was engineered to produce a particular acid, it also generated a toxic compound that’s not a natural component of tobacco.

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When bioengineers altered yeast to increase its fermentation, they were surprised to find that a toxin that naturally occurs at low levels appeared at levels 40 to 200 times higher.

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In summary, the use of viral promoters & particle bombardment make a mockery of nature & produce all kinds of downstream unintended consequences. Anyone that says natural cross-breeding & genetic engineering are the same needs to get their head examined.

/END THREAD

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