2-4-6-8, Novel Pairs to Replicate
Synthetic biology hit the front page of The New York Times earlier this month:
Scientists Add Letters to DNA’s Alphabet, Raising Hope and Fear
The article described a significant step forward in the use of "novel DNA." Two artificial nucleotides (X and Y) were added to E. coli, along with the usual A, C, G and T. The bacteria reproduced more or less normally, propagating the unnatural X-Y base pair until the supply of X and Y ran out. (That is touted as a safety feature.)
The publication in Nature by Floyd Romesberg, Denis Malyshev et al, from The Scripps Research Institute in La Jolla, California, and New England Biolabs, is titled:
A semi-synthetic organism with an expanded genetic alphabet
In the long run, some scientists hope for completely self-replicating artificial DNA, without the need for feedstock, and perhaps even “fully alien” with a completely different genetic system. (Romesberg calls that impossible, but he may be exemplifying Clarke’s First Law.) Fully functional artificial DNA remains at least a long way away; the same team first announced the replication of unnatural DNA in 2005, and formal discussion of "adding to the genetic alphabet” (Nature, 1990) goes back much further.
One result of developing this approach could be to produce far more amino acids (perhaps up to 172), and thus perhaps novel proteins. Romesberg told The New York Times:
If you have a language that has a certain number of letters, you want to add letters so you can write more words and tell more stories.
That’s a strained metaphor, and the Times story also notes that four could be the most efficient number of nucleotides anyway. However, the inevitable subhead, in this case to a good story at the well-connected U-T San Diego, becomes:
Scripps scientists widen genetic code within organism, unlocking the door to new treatments, other advancements
“New treatments” is a stretch at this point, but just in case they pan out, the Scripps team has partnered with Avalon Ventures to launch a company called Synthorx “to synthesize solutions for the discovery and development of novel therapeutics, diagnostics and vaccines.”
Other recent developments in synthetic biology include:
Twist Bioscience raises $26 million for tool to make artificial DNA — The gold, as usual, is in the supply chain, not the ore; Facebook billionaire Yuri Milner is among those investing.
Deal brings ‘humanized’ pig organs for transplant a step closer to reality — Craig Venter’s Synthetic Genomics, Inc. is partnering with Martine Rothblatt’s United Therapeutics.
A synthetic biology approach to improve photosynthesis — Bacterial genes may make plants more efficient “to ensure food and fuel security in the future.”
International consortium building synthetic yeast — Teams from the U.S., China, U.K., Singapore, India and Australia are cooperating in an effort to make the first synthetic version of a complex living organism; “better beer,” they say, which may be a mistake.
Synthetic Biology Still in Uncharted Waters of Public Opinion — the Woodrow Wilson Synthetic Biology Project finds support for medical advances but not for synthetic food.
Biotech industry cooks up PR plans to get us to swallow synthetic biology food — They prefer the terms “fermentation derived” (mostly true) and “nature identical” (shoot me now).
The Plan to Turn Elephants Into Woolly Mammoths Is Already Underway — If Stewart Brand can come up with the cash, nothing goes wrong, and a suitably adventurous elephant surrogate can be identified, George Church might show us a newborn mammoth-like creature by 2019.
Previously on Biopolitical Times: