FIGURE 6.

Principle of Single base chain extension (SBCE) (red dot = dideoxynucleotide; green star = fluorescent reporter; red line = anti-TAG). Specific detection probes are terminated one base before the polymorphic site. Utilization of fluorescently labeled dideoxynucleotides necessitates a separate reaction for each nucleotide in focus (minimally two). Target DNA hybridizes with probes after amplification but only the mix with the proper ddNTP leads ultimately to the synthesis of a labeled product, which is captured by anti-TAG on the microsphere surface.