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The word "How?" springs to mind at this point.
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Moneyed person who eats! Got allergies? Food sensitivities? Politically opposed to dairy? Hate saying "nut butter"? BUNGCO wants to help you eat without any of those worries!
Puree up a little bit of those eats in our proprietary buffer solution. Then our DNA test kit can detect DNA from the
10 common allergens including various nuts, dairy, wheat, soy and so on. And you will receive our catalog of other fine BUNGCO products and services targeting the food conscious.
"But wait!" you cry, in a thick accent. "I'm not allergic to anything, but I'm British! And I'm tired of being fed horse kidneys and getting told its beef kidneys!" We at BUNGCO will eat most anything, but like the British we enjoy it more if we know what it is. For you, an addtional kit to detect the 10 common food adulterants: rat, roach, fly, horse, human and so on.
And for the French and their sympathizers: the GMO detector kit. GMO can be detected by the presence of plasmids and other tools used to introduce the various foreign DNA sequences that make GMO foods delicious and easy to grow. Now if you suspect GMOedness in your caper flambee, simply check - and if found, refuse to pay and stomp off in a huff to collect mushrooms in the woods.
No BUNGCO kits use magic. Kits contain one or more short DNA sequences characteristic of target organism. Hybridization of DNA from food will produce color change noting detection of DNA from target organism.
SmartStax Corn product info sheet
many genes, introduced with either agrobacterium vector or microparticle bombardment [bungston, May 16 2014]
Golden Rice project
Agrobacterium vector [bungston, May 16 2014]
Bollgard II safety information
Particle acceleration method [bungston, May 16 2014]
Monsanto product safety info
[bungston, May 16 2014]
||Nice. A "royal food taster" for the 21rst century.
||But some foods are great because they are not
pureed. Nice layers of different ingredients. So, the
user would have to take enough samples of those
layers, with a skinny pincher to put in the BUNGCO
||BONUS: Could you use the same device to take a
small sample of a person to detect if they are full of
||Sort of baked. Food is often DNA tested (to see if
your tuna is legal, if your halibut is halibut, or if
your burgers are horses), but it's done by PCR
rather than by hybridisation.
||One of the problems is that food contains a lot of
crap (often metaphorically) which interferes with
assays. With PCR, you can detect much less DNA,
so you can dilute the sample to the point where
the crap isn't such an issue. Of course you can
also purify the DNA from the food first, but that
adds another level of hassle.
||You might do better to develop an ELISA-type
assay to detect specific proteins. You'd have to
mush the food up in water, then dip the testing
pen into it - like a pregnancy test. More
expensive to produce, but probably easier to
||(By the way, GM organisms shouldn't contain any
vector sequences. Given the regulatory hurdles,
GMers try to avoid introducing any uneccessary
DNA nowadays, even if it's inert or benign.)
||I am very skeptical that GMO do not contain vector. I cannot imagine any practicable way to get the vector back out.
|| Max if you can link me something besides this idea and your text that states vectors are somehow extracted from GMO after ferrying their cargo into the gene, I will compose you a tasteful and laudatory paen. And if you find nothing, I will accept an ode to my various halfbakings and their remedial effects on your own moral fiber.
||I don't know how they avoid vectors, because I
actually do GM in plants. My guess would be that
homologous recombination rather than old-style
||Given that there are now tailorable DNA cleaving
(such as CRISPA or zinc-finger-derived agents), I'm
sure they'd use homologous recombination. That's
they use to make most transgenic mice, I believe,
would be an obvious thing to do in plants.
||There are a range of other technologies and, given
desirability of not inserting vector sequences
regulatory perspective), I'm pretty sure they'll be
or the other of them.
||[EDIT - if you just Google "vectorless GM plants"
(no quotes), you'll get a ragbag of hits which will
point you in the right direction. I could dig out
some papers for you if (a) I could be bothered and
(b) you have access.]
||Darn. I was really hoping to see an example of " a tasteful and laudatory paen ". Do you have a template or an example we could see ?
||For anyone who didn't know what I was wittering
<begin lecture mode>
||Foreign DNA is commonly introduced into cells by
into small circular DNA molecules called plasmids
can be gotten into cells in various ways), or by
into a "dead" virus (in which case it can be
packaged up like
a virus, and gets into the cell in the same way the
normally does it).
||If you're modifying bacterial cells, you might just
things at that - the plasmid gets replicated
normal genome, and propagated from cell to cell.
However, the cells will eventually lose their
unless they carry genes the bacteria need. It's
common to put an
antibiotic resistance gene on the plasmid along
gene you're interested in; then the bacteria are
the presence of the antibiotic, and are obliged to
to their plasmids.
||In most eukaryotic cells (like crop plants), you
want your foreign DNA to be incorporated into the
rather than floating around on a plasmid, so that
stable in the absence of selection. A common
way to do
this is to include, on either side of your gene in
plasmid, stretches of DNA identical to the cell's
By various cunning means, you can persuade the
your plasmid to recombine - that is, it splices
the host genome between the bits of matching
||If this is done right, then only the gene of interest
introduced into the host cell. Newer techniques
to leave any other bits of the plasmid in the host
So, you should end up with a rice genome (say),
with only a
cauliflower gene (say) added to it.
||To get a new GM foodplant approved costs
$50M and, as far as I know, it's now virtually
do this if you've got various unnecessary bits of
as vector sequences or selection markers) left
||No, because people use lab strains which are
crippled in multiple ways. Sydney Brenner (one of
the dinosaurs of genetic manipulation) once
demonstrated the relative safety of this by
||By strange coincidence, I've spent yesterday and
today making kanamycin and chloramphenicol-
resistant E. coli - (that is, I'm actually putting in
something else, but Kan and Chl are the
selectable markers on the plasmids).
||The protocols for bacterial GM were developed
some time in the 1970s, and have been revisited
multiple times since then.
||As a point of reference, all the sequencing of the
human genome (and a lot of sequencing since
then) was done by cloning random fragments of
human DNA into bacteria. For the whole genome,
probably a million or more such clones were made
- a million GM bacteria, if you want to think of it
that way, each carrying an antibiotic resistance as
a selectable marker, and some random bit of
||Nut butter? Nut butter. Hmmm. Nutbutter.
||//then sees the word 'relative'.//
||[bigs], it's very sweet of you to be concerned for
all the scientists working on genomic and other
healthcare-related projects. And it's true that,
handling these things day in, day out in fairly
relaxed ways, they would probably be the first to
fall victim to some killer bug. Fortunately, as far
as I know, nobody's died of handling routine E. coli
or yeast clones, so this sort of stuff is probably no
more dangerous than, oh, say, coal mining or
||//inject spider leg DNA and some pavlovian
response// I'll assume here that only a deep
knowledge of the subject and long hours spent in
thought can give rise to such a profound apparent
misunderstanding of virtually the whole of biology
in a mere eight words.
||// profound apparent misunderstanding of virtually the whole of
biology in a mere eight words.//
||////Would it not be possible to inject spider leg DNA and some pavlovian response into wheat ? It would then march into a thresher when the dinner bell sounds. That would be terrifid.////
||:://inject spider leg DNA and some pavlovian response// I'll assume here that only a deep knowledge of the subject and long hours spent in thought can give rise to such a profound apparent misunderstanding of virtually the whole of biology in a mere eight words.::
||Max, I think the end of that second sentence isn't the typo you assumed.
||Yes, I spotted that. Give [bigs] the opportunity to
wind people up, and he'll wyndham.
||Yeah, that's all pretty basic stuff. We're working on
goldfish with extra wings.
||Re. the "Golden Rice" project, for which the link is
annotated "Agrobacterium vector":
||I don't know the ins and outs of the Golden Rice
project specifically, but the transferred DNA
(genes responsible for vitamin A synthesis, taken
[I think] from maize) will have been put into a
plasmid, and the agrobacterium will have been
used to get that plasmid into the plant cells. The
plasmid (which parts, I don't know) will then have
intergrated into the rice genome to produce a
stable transformant. In other words, the use of
agrobacterium to transfer the DNA is not relevant,
any more than the use of welding to build your car
means that you'll get burnt by driving it.
||Incidentally (and perhaps pertinent to another
thread currently running here), vitamin A
deficiency is believed to kill over 500,000 children
per year, mostly in developing countries. Golden
Rice contains enough vitamin A (and precursors
thereof) to provide the minimum necessary level
by eating a few ounces per day. The seed is
available free to farmers where it's most needed
(ie, in poor places), and Monsanto was the first
company to grant free licences.
||//Electric eel power cell - check//
||Oddly enough, I popped into the lab once over a weekend and witnessed
the arrival of a dozen or so large polystyrene boxes containing metre-long
||They're actually being used to study the ATPase that pumps electrons
(because they have shedloads of it in their electric organs), but a little
sideline in eelasers wouldn't be a bad idea.
||Though I prefer the spoon feeding of knowledge, larded with equations and witty prose.
||Second best is a gentle intimation of my own ignorance, followed by a nudge in the right direction.
||Perhaps with the knowledge that my own righteous indigation would fuel further reading.
||Which it did, and my fund has enlarged.
||I know that in addition to vector transformation, microparticle bombardment is indeed used to genetically engineer crops, and sometimes both with the results bred together. It is amazing on many levels.
||As promised, I honor Max, with his magnet in one hand and gold sovereign in the other.
||And thank him for helping keep the Halfbakery a place where one can learn.
||And obviously, I lack any sort of template for production of paens like this.
||Incidentally, horizontal gene transfer (ie, splicing of
genes from one species into another) is probably
fairly common in nature. Agrobacterium occurs
naturally, and can do this, as can many plant viruses.