Notice how emulsion PCR is different from Illumina's bridge amplification, but serves the same purpose of copying the DNA. This
approach is similar to Illumina's reversible termination. However, parellelized pyrosequencing uses emulsion PCR, in which an environment of small water droplets is created inside an
oil solution, instead of a solid surface as in reversible termination. Each "bead", or water droplet, contains
a DNA fragment, and PCR of the DNA fragment takes place in each droplet. Then,
similar methods of optical detection are used to sequence the DNA in each
bead. Each modified base, when incorporated, releases a
molecule called a pyrophosphate, which flashes detectable light in a series
of enzyme-catalyzed reactions. (38) (48)
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