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Enzymatic incorporation of a new base pair into DNA and RNA extends the genetic alphabet


A new Watson-Crick base pair, with a hydrogen bonding pattern different from that in the A·T and G·C base pairs, is incorporated into duplex DNA and RNA by DNA and RNA polymerases and expands the genetic alphabet from 4 to 6 letters. This expansion could lead to RNAs with greater diversity in functional groups and greater catalytic potential.

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Piccirilli, J., Benner, S., Krauch, T. et al. Enzymatic incorporation of a new base pair into DNA and RNA extends the genetic alphabet. Nature 343, 33–37 (1990).

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