Operator`s manual

37
Performing Gene Scanning Analysis
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Temperature Shifting ►
Click the Temperature Shift tab to reset the temperature axis (x-axis) of the melting
curves.
Eliminating the temperature offsets between samples can provide clearer
separation of samples that have subtle changes in their melting profiles. The
temperature axis of each curve is shifted in the region of low fluorescence (at
the end of homoduplex melting) allowing heteroduplexes to be identified by their
early drop in fluorescence.
The display on the Temperature Shift tab contains two graphs: the upper graph is
identical to the Normalized Melting Curves graph displayed on the Normalization tab,
the lower graph shows melting curves that are both normalized and temperature
shifted.
The upper graph has a movable horizontal slider that corresponds to the amount
of the Temperature Shift. Left-hand of the graph you will see a control field, labeled
Threshold, which can also be used to set the Temperature Shift level.
The default value of the Temperature Shift level is 5. You can change the value of the
Temperature Shift either by entering a value in the Threshold control field or by drag-
ging the horizontal slider on the upper graph.
Select a shift level that makes the curves form tight groups with the maximum amount
of distance between groups (as shown in the image below). For most applications, the
default level of 5 produces acceptable results.
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