Figure 1. Sequence from an unknown piece of DNA. A cycle single sequencing reaction was loaded into the Megabase sequencer, along with 95 other sequencing reactions. This is a typical set of chromatograms from one sequencing reaction. The bases were determined by automated software. Above the bases are numbers for the bases and below the four-colored traces the numbers indicated the number of scans by the laser. Below the bases is a horizontal line which remains horizontal at the 100 level (right side of Y axis) as long as the data quality is good. When the software detects low quality data (usually due to uneven spacing of the peaks), then the line dips down towards the 0 level. The color of the line starts off as blue but turns to brown to indicate the data should not be trusted which occurs at about base 886. G is green, C is black, A is blue, and T is red.
© Copyright 2001 Department of Biology, Davidson College, Davidson, NC 28036
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