The present invention provides methods, kits and compositions for high
fidelity nucleic acid amplification reactions of target nucleic acids
such that specific amplification products that incorporate non-standard
bases are produced. The amplification reactions can either be linear or
exponential. In some embodiments, the fidelity of the amplification
reaction is high enough such that a majority of the amplification
products maintain non-standard bases at specific sites designated by the
user after a specified number of amplification cycles. In some
embodiments, the ratio of non-standard nucleoside triphosphates is
greater than the amount of standard nucleoside triphosphates initially
present in the reaction mixture.