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Synthetic biology

New letters for life's alphabet

The five bases found in nucleic acids define the 'alphabet' used to encode life on Earth. The construction of an organism that stably propagates an unnatural DNA base pair redefines this fundamental feature of life. See Letter p.385

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Figure 1: Prospects for organisms that propagate unnatural DNA base pairs.


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Correspondence to Ross Thyer.

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Thyer, R., Ellefson, J. New letters for life's alphabet. Nature 509, 291–292 (2014).

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