Comparison of reversible terminator pyrosequencing using 3′-O-(2-nitrobenzyl)-dNTPswith conventional pyrosequencing using natural nucleotides. (A) The self-priming DNA templatewith stretches of homopolymeric regions was sequenced by using 3′ capped NRTs [3′-O-(2-nitrobenzyl)-dNTPs]. The homopolymeric regions are clearly identified, with each peakcorresponding to the identity of each base in the DNA template. (B) Pyrosequencing data usingnatural nucleotides. The homopolymeric regions produced two large peaks corresponding to thestretches of G and A bases and five smaller peaks corresponding to stretches of T, G, C, A, and Gbases. However, it is very difficult to decipher the exact sequence from the data.