Last week, bio-enterpreneur icon Craig Venter burst into the limelight yet again by announcing that a team under his direction inserted a chemically synthesized genome into Mycoplasma and succeeded in getting the resulting bacterium to propagate. The work duly appeared in Science and the predictable shouting ensued, from fears that humans are "playing God" to hails of "artificial life".
Several important issues got lost in the din. Let's leave the obvious potential objections aside - after all, humans started futzing the moment their frontal cortex became prominent and the consequences of this, intended and not, have decisively affected earth and all life on it. Instead, let's examine the clothes of this emperor closer up. To stick with the metaphor, Venter's latest is like exactly reproducing a large cloak onto a new piece of fabric identical to that of the original. It's not like creating a new garment or even cutting and pasting from previous garments to make a quilt, crazy or otherwise.
The Venter work is not a discovery, let alone a paradigm shift. It's a technological advance and even then not of technique but only of scale. The experiment is merely an extension of a well-known principle that every biology lab uses routinely: namely, that bacterial genomes can be modified almost at will (barring a few indispensable regions) and in such ways as to turn the bacteria into potent mini-factories for specific proteins. The Venter bacterium is actually pedestrian because it carries an exact duplicate of a naturally occurring genome. Its only artificial aspects are the molecular "flags" that its makers included in the synthesis to mark the artificial genome for further tracking - standard operating procedure in all such modifications.
Most decidedly, this is not artificial life (though I hasten to add that there is nothing mystical or long-term unknowable about components of living cells and organisms, including the eventual ability to tweak them). To propagate the synthesized chromosome, the Venter team used a bacterium whose endogenous DNA had been removed but was otherwise intact. This means that they used existing natural components to do the real task of propagation - the entire structure and machinery of the host cell. This makes the endeavor even less groundbreaking than injecting genetic material into a mammalian egg or stem cell (as was done to produce Dolly the sheep with far less advanced technology).
Lastly, this does not bring us a single step closer to engineering customized functions, from vacuuming up oil spills, excess CO2 or methane to producing chlorophyll or unique drugs. Creating a synthetic cell totally de novo is theoretically doable but far below the event horizon. Altering existing genes and/or creating ones for novel functions is more distant still, because making the coding part is only a small part of the task -- if we figure out how to get them to encode it, for starters. Persuading them to express at the right place and time is equally crucial. So is coaxing them to work in eukaryotic cells which, unlike easy-going bacteria, have carefully guarded compartments - the nucleus in particular.
In short, the Venter endeavor was expensive, glitzy - and banal. My advice to bioethicists is to save their energy for truly fearsome items, such as recombinant bacteria or viruses that may arise from species pushed together by abrupt dislocations of habitats (and for the inevitable push for a broad research-suffocating patent from this work). I've done far more "dangerous" work in my near-constant cloning than this sheep attempting to pass as a wolf... nay, a lion.
Note: This article is also on the author's blog, with two images that tell the whole story succinctly and far more eloquently than words.
"The Venter work is not a discovery, let alone a paradigm shift. It's a technological advance and even then not of technique but only of scale."
Sort of like saying that today's supercomputers are not a paradigm shift over the mechanical adding machine, or that nuclear weapons are scaled up firecrackers.
Many advances "only of scale" are indeed paradigm shifting.
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Your juvenile condescension is not an adequate substitute for real knowledge. And you can apply the jeremiads about emotionalism far more usefully to yourself.
Keep an eye on the ability to make and test thousands of varations on a single gene which will transform the world., making a single big piece of DNA is interesting, but not as immediately useful. for the foreseeable future ( 10 years? Hah!) any large scale engineering of chromosomes will require testing each of the parts and putting them together, so copying a slightly altered version of natural chromosome is (just) a demo project. The real fireworks are yet to come. Take a look at companies like Verenium which have been making designer enzymes for years.
Example: lupus is a genetic disease, but may only affect one of identical twins, not the other.
Both twins were found to have identical DNA, in the "non-junk" part.
But the twin with lupus had less "methylation" marks in the so-called junk part.
DNA does not determine what we will become, or even what proteins are produced.
"Methylation" takes place in the womb (and after) to strengthen or disable genes.
Most compelling: methylation can be passed to the next generation.
Traits determined by environment can be inherited.
LAMARCK WAS RIGHT !!
EPIGENETICS is the new frontier.
http://en.wikipedia.org/wiki/Epigenetics
http://en.wikipedia.org/wiki/Methylation
Genes encode catalytic, structural and regulatory proteins and RNAs. They do not encode the nervous system; even less do they encode complex behavior. At the level of the organism, they code for susceptibilities and tendencies — that is, with a few important exceptions, they are probabilistic rather than deterministic.
No reputable biologist suggests that genes are not decisively involved in outcomes. But the constant harping on trait heritability “in spite of environment” is a straw man. IThe nature/nurture debate has been largely resolved by the gene/environment (GxE) interplay model, a non-reductive approximation closer to reality. Genes never work in isolation but as complex, intricately-regulated cooperative networks and they are in constant, dynamic dialogue with the environment — from diet to natal language.
More on this topic here: Miranda Wrongs: Reading too Much into the Genome
http://www.hplusmagazine.com/articles/bio/miranda-wrongs-reading-too-much-genome
All reputable biologists believed that there were only some 80,000 real genes, the rest was junk DNA. They were wrong.
I disagree. Epigenetics has disproven major, even sacred, tenets of biology.
You should all apologize to Lamarck, or his descendants, or any adherents who braved your collective ridicule all these years.
I am a scientist myself, so I know how arrogant we are. And never wrong :-)
"there have been some observations of transgenerational epigenetic inheritance (e.g., the phenomenon of paramutation observed in maize). Although most of these multigenerational epigenetic traits are gradually lost over several generations, the possibility remains that multigenerational epigenetics could be another aspect to evolution and adaptation."
Translation: changes caused by environment can be passed on to multiple generations, though their effect fades. (Now, don't tell me that's what you would expect - genes don't fade away!)
"These effects may require enhancements to the standard conceptual framework of the modern evolutionary synthesis."
Translation: Lamarck was right, we need some "enhancements" to also be right.
A bacterium that breaks down petroleum might seem like a good idea, especially with the current BP crude catastrophe in the Gulf of Mexico. But do we really want a voracious consumer of hydrocarbons on the loose? You won't think it's funny when it gets in your gas (petrol) tank, and in the filling station down the road, and the refinery in your region.
I don't think we understand enough yet about the integrated functioning of entire genomes to be playing with this sort of thing.
At the same time, we have already done significant genetic engineering at different scales for a very long time. Believe it or not, we're actually good at it. And biologists, at least, are extremely aware of the lurking dangers. The bacteria we engineer can barely survive outside the lab, they're pampered critters -- though horizontal transmission is always possible.
The bigger problem is that our technology has allowed us to reach such numbers that only more technology will prevent a huge collapse. Remaining humane and retaining as much wellbeing, environmental integrity and biodiversity is clearly going to be a challenge.
" The bacteria we engineer can barely survive outside the lab, they're pampered critters"
and genetically modified crops--are they also simply "pampered critters" ???
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be able otherwise to break down other carbons- Trees, humans, plastics etc. a miscalculation here can turn all carbon based lifeforms on earth to dust!
It's not on video and no one has had the good sense to do a remake but Spacemaster X7 was a good film. There was a disease organism from a space probe that had a collector. The scientist who had had this installed (over peers' rejection of the concept) was analyzing it in his home lab. His jealous girlfriend shot him. His body was completely consumed. The microbe ate all protein. The girl was on the lam, changing her identity and appearance and infecting people she met. She was a Typhoid Mary, a carrier who is not immune but in symbiosis with a disease. The rest of the film is the detectives trying to find a woman escaping from city to city with no knowledge that she is spreading a new disease. The detective eventually corners on a plane and explains it to her and the plane is brought back for quarantine. He acknowledges to her that quite likely he and everyone on the plane will be dead -- and dissolved to foamy slime -- in 2 more days.
Not on video as far as I know. Surprisingly intelligent low-budgeter.
Ridley Scott, are you listening?
I downloaded the article and associated commentary from the Science magazine web site (they are providing these articles free of charge). So far I've only skimmed this material, but what I've determined is that they have probably made some technical breakthroughs.
First, they brought the fidelity of cell-free DNA synthesis to a new, higher level. They assembled a million base pair sequence, and only obtained something like 39 errors. Second, they needed to propagate all of this DNA in yeast, while keeping it inert.
Those are gains of degree, not of kind. No one needs to be having a great new philosophical debate as a consequence of this article.