Distinguishing Single Nucleotide Polymorphisms of DNA Using Fluorescent Oligonucleotide Probe Containing 2-Aminopurine

Abstract

The fluorescence intensity of double-stranded DNA (ds-DNA) hybridized by fluorescent 2-aminopurine (2-AP) oligonucleotide probe and different mismatched bases was studied by fluorescence spectra in this paper. The experiment designed and synthesised four oligonucleotide sequences with the bases of adenine (A), cytosine (C), guanine (G), thymine (T), and determined the fluorescence intensity of the mismatched double-stranded DNA. The results implied that the fluorescence intensity of oligonucleotide probe was varied due to different mismatched bases. And the fluorescence intensity was 546.9 with the ratio of 3.13, which showed a significantly increase as the mismatched base was A. While the mismatched base was T, the fluorescence intensity quenched to 43.26, as the ratio was 0.25. For C and G, the fluorescence intensity of 2-AP was 99.14 and 89.03, respectively, which showed a different degree of reduction.