This paper describes the design of terminal-mismatch discriminating fluorescent oligonucleotides (TMDFOs). The method is based on the use of sets of oligo-2′- deoxyribonucleotide probes linked via their 5′-ends, and varying-sized flexible polymethylene chains, to thiazole orange, with the linker being attached to the benzothiazole moiety. The sequence of each set of labelled probes was identical and ...