Detection of one base mismatch using photochemical ligation.

We attached anthracene molecules covalently to one end of oligodeoxyribonucleotides to form three pairs of anthracene-ODN conjugates. The sequences of each pair of the conjugates were designed to bind adjacent sequences of the template with the anthracene units directed such that they stacked each other. The conjugates dimerized only in the presence of the template by light irradiation. We found that the ligation yields largely depended on the substituted position of anthracene groups. Sequence selectivity in the dimerization yield was preserved even in the system with highest reactivity. SNP bases could be discriminated rapidly by combining the techniques of MS spectroscopy.