Figure 2.

Mismatch detection using synthetic oligonucleotides as targets. Four primer elongation reactions were performed with a 50mer oligonucleotide carrying a central single nucleotide exchange, in each reaction. Oligonucleotide primers spotted as duplicates on the microarray, consisted of a 5′(T)₁₅ spacer sequence linked to a 25 bp specific sequence complementary to the 25 nt at the 3′-end of the targets and carried one of the four bases at their free 3′-ends. Positions of the primers with the respective variable base are indicated above.