a Methods Useful in Genelics and Oncology
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Temperature Ie)
Fig. 4. Effect of amplification cycle number on derivative melting curves of PCR products using
SYBR Green 1. The relative area of the two peaks changes as PCR amplification progresses. At 35
cycles (blue) the lower peak is predominant while both lower and upper peaks are of approximate
equal size at 40 cycles (red). At 50 cycles the upper peak (black) is much larger than the lower
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Temperature Ie)
Fig. 5. Effect of the temperature interval analyzed on the resolution of derivative melting curves.
Two closely-spaced peaks in a normal heterozygote are apparent when 1.1 0 C are averaged on
the LightCycler software (solid red line). Only one peak is apparent when 3.1 0 C are averaged
(dotted red line). In a Huntington's heterozygote, the alleles are widley separated in Tm and distinct peaks are apparent when analyzed either with LlOC (solid black line) or 3.1 0 C (dotted
black line) intervals