Incredible news I read today.
Be sure to read the article in its entirety… after you read this post of course. So you should know hopefully that all life on earth seemingly exists only to propagate their genetic information to the next generation… information written in a chemical language called DNA. The alphabet of this language has 4 letters or bases, A T G C, which stand for 4 distinct chemical compounds, Adenine, Thymine, Guanine and Cytosine. Each cell of the human body contains a DNA sequence that is approximately 3.2 billion base pairs, (pairs because DNA is almost always present as a pair of strands twisted around in a helix).
That pretty much sums up all life on earth from bacteria to rats to pterodactyls to humans… all life we have ever known to have existed has the exact same genetic makeup made up of ATGC bases pairs.
Apparently, at Scripps Research Institute in La Jolla, scientists have created E.coli (a kind of bacteria found literally everywhere, cows, humans, food poisoning, and most, if not all, labs), with 6 letter in their DNA, ATGC and “XY”.
I will not go into further journalistic detail, you can read the details in the link above, but goddamn that is awesome. As one of the scientists also says, the fact that it is even possible, that the bacteria don’t either just die or auto correct the “error” in the DNA is amazing.
Moreover, a few years ago, they were able to coerce the Ecoli into making proteins that are not found in nature at all. Now they can produce more than a 100 different amino acids, besides the select 20 that all life on earth otherwise uses.
Philosphically, what does this mean?
The broader meaning seems to be that DNA material/protein material/amino acids – the stuff of life – are not as selective as we thought. Perhaps the 4 bases and the 20 amino acids that encode all of life as we know it, were simply chosen by chance. This means that if indeed we encounter extra terrestrial life, someday in the future, it may be nothing like we know, completely different right from the building blocks. On that note, if many unique kinds of genetic information can be found to be viable, then perhaps spontaneous emergence of life is not as unlikely as we currently believe. So the prior probability of existence of alien life just got bumped up a few orders of magnitude.
However, there could be practical applications of this that are very strong. Normal bacteria are already used to our advantage e.g to manufacture antibiotics, clean up oil spills etc. Engineered bacteria, which have some genes manipulated are also used to produce some protiens that we like. But bacteria that are engineered to be completely a new form of life, extraterrestrial, could in theory in a similar way to make completely new chemicals that we don’t even find naturally.
I am paranoid, tell me the bad news?
Ok so far so awesome. Is there any downside? Well I am reading Stephen King’s The Stand right now. Its the one where an artificially engineered virus or bacteria is released from the army labs by mistake and proceeds to wipe out most of human life save a few individuals who are immune to it. I don’t know how it ends, I’m still reading. Could that happen here? Can an artificial bacteria wipe out humanity?
Hmm… I am not a biologist, and that invalidates most of what I can say about the issue right away. Yet I find the urge to pull opinions out of my ass irresistible. So here goes.
Less than 10% of all bacteria found on earth cause diseases and most microbial activity doesnt kill people. Fatal pathogenicity is not particularly great for the microbe either, after the host dies, the bacteria would need to find a new host. Evolution would much more prefer symbiotic organism which learn to live with the environment rather than destroying it. The few pathogens we have get around by either lying dormant when they are outside the host or, more commonly, exists symbiotically in nature already but are harmful to humans under certain conditions.
|Classic US Govt, messes up and kills millions|
If our artificial bacteria ever finds its way out of the lab by accident, in all likelihood it will not be able to survive without the necessary symbiotic tools to survive that normal bacteria have evolved over millions of years. However that said, the fact that it did not evolve to coexist with other life would be the exact characteristic that would also cause an artificial microbe to wipe out all humanity if it could somehow persist in nature.
So… I guess I personally think its possible. The odds might be astronomically small, or not. I don’t know, someone with more knowledge should comment on this. More importantly though I don’t think any one in their right minds would leak something like this into the environment. Simply because the sheer number of variables in a real biological environment are too many to keep track of, the effects of mutations and competition are more complex than can be simulated exactly.
That is one science fiction prophecy that had better not come true.
I’m only a quarter done and its pretty awesome
One of my old so-silly-its-watchable movies that I like.