of these. Using the old strands as templates and following basepairing rules, polymerase catalyzes the addition of nucleotides into complementary sequences. Another enzyme called ligase then joins these pieces into whole complementary strands while matching them to the original templates. Sequencing-by-synthesis methods simulate parts of this process on a single DNA strand of interest. As bases are added by polymerase to the starting point of a new complementary strand, known as a primer, or recognized by ligase as a match, the template’s sequence is revealed. How such events are detected varies, but one of two signal