Scripps Research Institute scientists have created an "alien life" form that replicates itself in a cell, opening the door for creating new medicines, antibiotics, vaccines, and eventually an unforeseeable number of biological tools and products, Nature reports.
After a 15-year effort, the researchers proved it was possible to move beyond the confines of the A, C, T, and G, and expand the chemical alphabet that can be used to create replicating base pairs. These new alien base pairs are quite unlike the naturally occurring ones that make up life on Earth.
“What we have now is a living cell that literally stores increased genetic information,” says Floyd Romesberg, the project leader at Scripps.
"This is the first time that you have had a living cell manage an alien genetic alphabet,” Steven Benner, a researcher at the Foundation for Applied Medicine who has long been working on the same problems, tells The New York Times.
Romesberg is eager to prove that this innovation has practical applications. He has co-founded a new company called Synthorx, which also launched yesterday and will aim to use the new technology to discover and develop new medicines, diagnostics, and vaccines. Synthorx has already reeled in investments from Avalon Ventures and Correlation Ventures.
The methods the Scripps group used to get its new letters into existing DNA was innovative. They used a gene from a diatom to engineer an E. coli bacterium that would let a new plasmid they had created into its cells, and after steadily feeding the alien plasmid into the bacterium's cells for a couple of weeks, eventually it started creating the plasmid on its own.
Sprinkling in the two new letters to the alphabet soup of life could make all sorts of things possible.
"If you read a book that was written with four letters, you’re not going to be able to tell many interesting stories,” Romesberg says. "If you’re given more letters, you can invent new words, you can find new ways to use those words and you can probably tell more interesting stories."
The Times also notes that the creation of an alien life form could have many "far-reaching ethical, legal, and regulatory implications," according to Jim Thomas of the ETC Group, which has contested the safety and ethics of synthetic biology research and genetic engineering.
"While synthetic biologists invent new ways to monkey with the fundamentals of life, governments haven’t even been able to cobble together the basics of oversight, assessment or regulation for this surging field," Thomas says.
Romesberg and his team are not sure what would happen if the bacteria contained many of the new pairs, or how long they would survive, as the group only grow their bacteria for 24 replications over about 15 hours, The Times notes. Importantly, they also have not demonstrated that these artificial nucleotides can be transcribed into RNA and used to make proteins.
But the news comes as a major step forward for science and toward enhancing genetic engineering.
"It is clear that the day is coming that we’ll have stably replicating unnatural genetic structures," Stanford University chemistry Professor Eric Kool tells The Times.