Life on Earth has relied on four DNA subunits – G, T, A and C – for billions of years. However, US scientists have now created two new letters of the DNA alphabet ‘X’ and ‘Y’, encoded into living, breathing – and dividing – E. coli cells. Lead researcher Floyd Romesberg claims it’s all perfectly safe, preferring to think “If you read a book that was written with four letters, you’re not going to be able to tell many interesting stories. 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.” But will all of these “interesting” stories have happy endings?
For now, the new X/Y DNA does nothing. But what this new alien genetics does, is open up the potential possibility of creating new amino acids, proteins and enzymes − and new ‘alien’ life-forms, never before seen in nature – with new unpredictable outcomes. Here, the engineered microbe – E. coli − is a type of human gut bacteria. So if something goes wrong, we humans will probably be amongst the first species on Earth to be affected.
One could argue that ethical questions about where to draw a line around how far synthetic biology research should go, and acceptable risks – have gone from “where to draw a line” – to “whether anyone is going to bother to draw a line at all?”…
