We live in a world transformed by our ability to manipulate the nucleus of atoms. Nuclear power plants provide abundant energy without polluting the air, yet on the other hand thousands of nuclear warheads sit in multiple countries ready to annihilate everything, even if it’s not on purpose. There are an uncountable number of other ways that humanity’s dive into nuclear chemistry has impacted the lives of people across the world, from medical imaging equipment to smoke detectors and even, surprisingly, to some of the food that we eat.
After World War 2, there was a push to find peaceful uses for atomic energy. After all, dropping two nuclear weapons on a civilian population isn’t great PR and there’s still a debate on whether or not their use was justified. Either way, however, the search was on to find other uses for atomic energy besides bombs. While most scientists turned their attention to creating a viable nuclear power station (the first of which would only come online in 1954, almost ten years after the end of World War 2), a few scientists turned their attention to something much less obvious: plants.
Normally the way that evolution works is that, by random chance alone, a gene changes in a way that helps that species survive and procreate. Genes are modified all the time, whether by errors copying genes or from external causes, and most of the mutations are harmless or can be repaired by the organism. Even then, unless the mutation occurs in the reproductive cells, the change won’t be passed on to offspring. So, evolution occurs extremely slowly on the very rare chance that a mutation occurs in a reproductive cell that is passed on to offspring, and that gene is beneficial to the organism in a way that allows it to be passed on further.
The “external cause” is the interesting part here. Usually, the external cause is ionizing radiation (although there are other methods outside the scope of this article) and unless it kills the cells there is a small, small chance it may introduce a useful mutation. The Atomic Garden enthusiasts, such as C.J. Speas and Muriel Howorth, realized that atomic energy could be used to speed along the “useful mutation” process, and set about irradiating as many plants as they could get their hands on in order to cause as many mutations as possible. Presumably, many plants were harmed in this process.
The idea that Speas and Howorth (the founder of the Atomic Gardening Society) had was that irradiated plants might change the world by producing plants that were more resistant to disease, produced more consumable food, or grew faster. This latter trait was demonstrated in England by Howorth. After throwing a party in praise of these new cultivars, she encouraged her guests to eat some of the peanuts that were produced in an atomic garden. Her guests were impressed, but didn’t eat them all. Howorth decided to plant the remaining peanuts to see how they would grow, and found that they grew like “magic beanstalks“. Journalists came from all around England and praised her peanut plants as “the most sensational plants in Britain.”
It’s interesting to note the excitement of the time for this novel use of radiation. Contrast this with today, where most of the press concerns themselves with reporting on nuclear disasters, nuclear protestors, and general armageddon caused by nuclear energy. Indeed, without the work of Speas and Howorth and the enthusiasm for nuclear energy that they and many of the time had, it’s likely that radiation gardening would have been a forgotten science experiment of the 1950s.
In what is likely the only surviving radiation garden remaining today, but is similar to what was done in the 50s, a radiation source (in this case, cobalt-60) is placed in the center of a circular field. Various plants are placed around the pole at varying distances in an attempt to introduce useful genetic variations. Once one is found, that plant is bred back with a non-irradiated plant to cultivate the desired trait in future generations of plants. This breeding process ensures that we’re not eating irradiated grapefruit, for example, and also ensures that we can continue to produce the gene in a controlled manner instead of hoping to get a delicious piece of fruit every time we set a plant down beside a block of radioactive cobalt.
There are many thousands of breeds of plants in existence today because of radiation gardening. They may have been gifted with the ability to withstand pests such as fungus or insects, or they may have produced a more desirable fruit or a higher yield. There may even be plants alive today with mutations caused by radiation that we don’t know about, thanks to some members of the Atomic Gardening Society simply selling irradiated seeds to the general public in the late 50s.
Now, of course, scientists have the ability to splice specific genes directly into an organism which is a much more controlled and reliable way of introducing new traits to an organism. Not only that, but it allows for a greater range of possibilities like adding DNA from bacteria into a plant to increase it’s resistance to pests. Radiation gardening has fallen out of favor for other methods such as the use of a gene gun, which allows scientists to literally shoot genetic information from one source into the cells of another organism. This is a much cheaper way as well, as it doesn’t require an entire field (and a presumably expensive radiation source), and it can be done on any organism instead of only on plants. They can also be used in other ways, such as delivering DNA vaccines and helping to research neurodegenerative disorders.
For the technology available in the 50s, however, radiation gardening was the best way to go about introducing new traits into crops. Even though by today’s standards we’d consider it more of a “spray and pray” method of introducing beneficial mutations to a crop, it was enthusiastically received at the time and delivered results, many of which we still eat today. Indeed, without the efforts of the scientists who hacked a biological system with an energy source, we would likely have a larger problem feeding the rapidly increasing population than we do today.
It makes me laugh that cultivars produced by artificial mutagenesis are not considers GMOs by most definitions of the term. Apparently random effects to the germline are considered safer by some than specifically engineered ones. Go figure.
If you think about it, thats kinda how it is in nature. Some years in plant history may have had high solar activity and more ionizing radiation at play for outdoor plants. This is why I believe indoor self-contained cloning with a minimal nutrient list produces the purest results. Outdoor has varying sun, soil purity, rain purity, pests, pollution, etc.. organic yet less pure.
It would be interesting to see how the most effective radiomutagen dosage compares to solar flare radiation levels. My feeling is that solar flares would still be well under the radiomutagenic dose found useful in technology.
Unintended consequences of plant transformation: a molecular insight
https://www.researchgate.net/profile/Marcin_Filipecki/publication/6665561_Unintended_consequences_of_plant_transformation_a_molecular_insight._J_Appl_Genet/links/53ecb4cc0cf24f241f159a04.pdf
Assuring the safety of genetically modified (GM) foods: the importance of an holistic, integrative approach
http://cib.org.br/wp-content/uploads/2011/10/estudos_alimentares19.pdf
The difference is largely one of time, and one argue that natural radio-mutagenesis from NORM has made some contribution over the course of evolution however you are correct that as a source of useful novel strains it is a very minor factor.
As for safety the fact is that this has been an issue from the very beginning of managed breeding of plants: there are several cultivars that have been developed from families with toxic members, and no doubt there were cases of poisoning from breeding efforts that have been lost in time. In other words it is not a new problem, or one that those developing novel strains were unaware of until recently.
If one can make the argument that exposing seed to radiation from a cobalt-60 source is analogous to exposure to NORM then I submit that viral DNA insertion techniques are as well because that too happens occasionally in nature. The fact is that most that object to GMOs cannot elucidate a consistent definition of what a GMO is yet will thunder about what they imagine are the potential dangers which again they have problems describing in any detail.
I agree. The mutations would happen anyway given a long enough timeline.
Which ever way a type of plant trait is created putting it into mass production should be done with care because it may eliminate or contaminate otherwise useful strains with a proven track record of traits already selected. Remember Starlink corn? It produces a natural insecticide that is harmless to the robust bovine digestive system but it is nearly inedible for humans. It still contaminates the seed corn to this very day over 10 years later.
To play devil’s advocate, natural viral DNA insertion is random; the same way that radiation exposure is. Plants that survive a viral DNA insertion still have to keep that mutation through generations in the wild before being introduced en masse into the food chain. GMO virally manipulated plants enter the food chain much faster.
So what? Simply keeping a sequence through many generations does not guarantee that it is harmless to humans and safe for consumption. Since the objections to GMO are currently centered on food safety it should make little difference if a novel hybrid is created by natural viral insertional mutagenesis or artificial. The fact is that the risk human health is marginally greater in the former case, as the naturally occurring example will not be subject to the same degree of scrutiny in this regard as the latter.
Any claim to the effect that artificial techniques that are identical to events that can happen naturally (however rarely) are more dangerous is illogical.
You’re right, I’ve looked into this before and there is little concern among academic research journals. The general assumption is something like, humans would taste anything naturally present that could have been amplified in concentration and that was bad.
It really is sad/surprising that a link didn’t appear to the: International Atomic Energy Agency — Mutant Variety Database:
https://mvd.iaea.org/#!Search
You can find products sold at places like Whole Foods and Trader Joes! Ha!
Yep. Pink grapefruit is one of those.
At one point, as I recall, there was a wasp nest constructed on the Co60 source at the center of the illustrated “crop circle”. They seemed unaffected. The Co60 source consisted of many Curies – quite intense gamma exposure levels at its surface (MRads).
There was a Gilligan’s Island episode about this. The irradiated plants gave everyone super powers (not including the power to be rescued). Sort of like being bitten by a radioactive spider.
in ’74 a new wheat colture was created in Italy with the name of “Creso”, it’s not a GMO but it was irradiated with gamma rays and later on mixed with an american species. From that colture comes what it’s called “grano duro” (durum wheat). It’s a small type, it’s stronger and resistant and now the main type used here for producing pasta (80-90% share).
> From that colture comes what it’s called “grano duro” (durum wheat).
Uhm. No. Triticum turgidum durum (“pasta” or “hard” wheat) existed long before people used it for pasta…
What you’re talking about is one selected line that was crossed due to its better resistance against certain plant diseases (e.g. fusarium).
Gen gun is far too random. This is the new trend: https://en.wikipedia.org/wiki/CRISPR
Instead of a block of cobalt or whatever, isn’t there an easier way to introduce random mutations to a bunch of seeds? Like X-Raying a packet of heirloom tomato seeds before planting?
The idea is to just lightly scramble the DNA before test-growing the plant, right?
I keep meaning to build an ultraviolet irradiation chamber for small seed mutagenesis. The general idea is to mutate them to the point where you have a ~50% reduction in germination, then screen/select heavily the resulting plants for interesting (by whatever definition) traits.
You would want to be working with much larger numbers than a single packet. It would take some trials to determine the correct mutagen dosage/exposure and then you’ll be explicitly killing half of them, with another large fraction would probably turn out inviable at stages later than germination.
Plus with UV you can eat the produce of the original plant, instead of making it radioactive and having to wait a generation.
Xrays wouldn’t make the resulting plant radioactive. Now, if you’re dosing the seeds with radium to get your mutations… you might want to find a different strategy.
Nor would gamma rays.
Gamma rays from Radium wouldn’t, but Radium itself would.
You might want the seeds to be metabolically active (starting to germinate) when they’re being irradiated, so the physical damage can be repaired and thus set any DNA damage that the irradiation has caused into actual mutations. This might allow you to recover more viable, but mutated, seedlings vs. bashing at them while they’re inert in the basic process.
UV instead of Xrays because UV induces point mutations, while Xrays tend to break DNA. Also, UV is a bit easier to keep contained after generation. The chromosome abnormalities resulting from intense X-rays can be useful in breeding a plant strain that is genetically incompatible with other varieties, or in studying the location of genes relative to chromosome maps, but these are pretty intense research projects for a home bio-hacker.
my guess is mutating germinating plants would be a bad idea since you would create chimeras rather than hybrids because some cells in the plant would be mutated and other wouldn’t be making it almost impossible to identify mutated plants as a whole let alone breed back to try to pass the mutation on to the next generation.
This is a fair point, but one that would apply to mutating seeds as well. One would need to grow out the treated seeds, then screen the second generation plants to get around this issue.
So: Mutated seeds -> M1 generation -> 2′ seeds -> M2 generation (screen here)
Something like http://hackaday.com/2014/11/24/a-uv-lightbox-for-curing-prints/ is what I’ve been imagining. The rotation motor would be replaced with a vibration source, so the seeds would shift about randomly in their tray and be more uniformly exposed. It might be good to have the UV source be more like UV-C (germicidal, ~250nm) to produce a higher level of mutations, but regular UV might work fine with longer exposure times.
395-405nm is UV-A which would be sub optimal for scrambling DNA
You would really need UV-C to shred DNA (luckily for all life on earth it is completely absorbed by the ozone layer and as it passes through the atmosphere and is absorbed it creates Ozone)
Sorry just clicked on the link and read there, didn’t notice that you mentioned UV-C until after I posted.
Dagnabit. I somehow managed to click on the report comment link. sorry.
After looking more into it, the difference between UV-A, UV-B, and UV-C would be in the spectrum of mechanisms of mutations generated. UV-C is more likely to induce pyrimidine dimers and break DNA directly. UV-A and UV-B are more likely to generate reactive oxides/hydroxyls that can then alter DNA bases in various ways. They would both have their place, experimentally. I suspect I would want the lower-energy UV-A/B because I don’t actually want to have the chromosomes in my subject seeds shredded. (If I wanted to produce plants with all sorts of chromosomal rearrangements that might interfere with crossing to other varieties, etc… then yes, UV-C would be the choice.)
But… now that I think about it more… DNA breaks are likely to be repaired by non-homologous-end-joining mechanism, which will involve the loss of a small number of bases at the break site. This is more likely to result in the inactivation of an impacted gene than a simple point mutation. This would make for more obvious mutations.
Low energy UV -> increased point mutations.
High energy UV -> increased gene knockouts and chromosome rearrangements.
If you’re looking to increase genetic diversity, use UV-A/B. If you’re looking to find dramatic phenotypic changes, use UV-C.
It will probably take some experimentation to determine if there is any reality to this insight. Most research on UV mutagenesis in plants seems to be discussing pollen; small seeds are wide-open territory. Fortunately, UV-B and UV-C sources (LEDs and germicidal lamps) are readily available.
In other words: UV-B if you want redder tomatoes. UV-C if you want tomatoes with wings.
Won’t work. The rays need to penetrate the epicotyl.
Some UV does should get through, but at a much attenuated level.
uh, UV is non-penetrating radiation. It can’t get through the seed case to the “germinating” DNA. UVC is germicidal only if the “germs” have direct exposure through a transparent medium (like vacuum, air, thin layer of water). One needs X-rays, gamma rays, or really energetic particles (alpha, beta, neutron, etc.) to get to most seed DNA. UV-C might work slightly on tiny, tiny seeds in really high dosages.
UV-C goes right up to what we then call Xrays. Tiny seeds in really high doses is exactly what I’ve been thinking of.
Now that sounds like a fun project, if you do it you have to write a HaD article!
In experiments like that garden featured in the image above, they would irradiate during seed formation (or at earlier stages like pollen/egg formation), then once seeds were formed they’d dry (if that plant required it) and grow the seeds in non-radiative environment, lethal mutations would obviously not make it, and of the survivors they’d screen for increased positive/interesting/desired trait enhancement.
All hybrid plant varieties made using cross-pollination are genetically modified. In some varieties the new variety is fertile and passes the desired traits to its seeds. Usually they are either infertile, producing seeds that won’t germinate at all or the seeds produce only some or none of the hybrid traits.
Another way, often used in fruit trees, is to plant a lot of one variety of tree that produces no pollen and some ‘male’ trees of a related but different variety, or ones that are self fertile so excess pollen will be carried by wind and insects to the other trees. Fruit produced by the pollinator trees is usually not saved.
Apples are especially uncooperative when it comes to passing on their genes unaltered in their seeds, so desirable varieties from irradiation or cross-pollination are perpetuated by grafting. http://www.thedailybeast.com/articles/2010/01/22/the-secrets-of-hybrid-fruit.html
Red grapefruit is a product of irradiation, one of those chance mutations that happened without any negative effects. But over the years the red trait has been fading. Each generation of that cultivar is self correcting the mutation more and more. So there are some projects ongoing to restore the deep red color from the original mutation.
“…a radiation source (in this case, cobalt-60) is placed in the center of a circular field. Various plants are placed around the pole at varying distances in an attempt to introduce useful genetic variations.” We need to put up a radiation pole in Washington, D.C. to see if the introduced mutations will produce a smarter government. Gawd knows we need it!
Ahh I’d love to see the faces of all the anti-GMO/Organic nutbags on Facebook when confronted with the fact there’s atomically mutated plants in the foodchain….
I read about this a couple of years ago, a friend who is a gardener wrote an article about it on her blog. It is very interesting, and certainly an example of how people thought of our little atomic friends back in the day. Even a good while after Marie Curie died from cancer.
As far as feeding the hungry though, that’s a red herring, used as an excuse by all sorts of agribusiness to justify what they do, just in the pursuit of profit. There’s already enough food to feed everyone in the world. It’s finance that makes people starve. Banks making predatory loans to unreliable “governments”, military juntas and the like. The “government” spend it on palaces and machine guns, get deposed shortly after, and the country’s people are stuck with “their” debt. With all sorts of horrible threats if they don’t cough up the money.
The “Drop The Debt” campaign a few years ago explained all this. The original loans have been paid back many times over in interest payments, but the interest is such that countries don’t get a chance to make a dent in the original loan amount. Which of course is the plan.
That’s why people go hungry and die. Because rich people take their money. There’s also the issue of Africa’s rich mineral rights being exploited by Western mega-corps, and rich countries toppling democratic governments in favour of despots who’ll do as they’re told when it comes to letting businesses act how they like.
That’s where poverty comes from.
While you are right in stating that hunger is currently more a distribution rather than a production problem, it needs to be recognized that the reasons that there the are surpluses that make this so is that agricultural science has kept ahead of population growth, and to maintain this lead, it must look to direct germline modification. While indeed the cultivars we now grow meet our needs the fact remains that susceptibility to disease, shifting climate, and environmental damage caused by the chemical inputs some of them need to thrive creates vulnerabilities that need to be addressed now if they are not to become potential disasters in the future.
once upon a time, a monkey picked up a glowing rock and kept it too close to his happysack. then humans happened. the end.
this is so amazing!!!