There are two kinds of mutation detection methods: specific and scanning. The former is used to identify specific, well-characterized sequence variations, while the latter one is used to detect uncharacterized sequence mutations. SSCP is an example of mutation scanning technology. Mutation detection via conventional SSCP requires PCR* amplification of the DNA fragment of interest, denaturation of the double-stranded product, followed by non-denaturing slab gel electrophoresis. The need for higher efficiency detection, greater automation and safety have led to studies using capillary electrophoresis-based SSCP analysis.
Figures 1(a) and 1(b) illustrate examples of CE-SSCP profiles derived from both the wild type and mutant 185delAG alleles. As shown, the profiles for both the forward and reverse strands of wild type are qualitatively similar [Fig. 1A (a) and (b)], as are those for the mutant 185delAG allele [Fig. 1B (a) and (b)]. Most important, there are consistent qualitative differences between the wild type and the mutated strands in the profiles. These differences are manifested in the form of three peaks in the SSCP profile of the wild type, where there are five peaks in the SSCP profile of the mutant allele - allowing the wild type and mutant alleles to be easily discriminated via visual inspection (Click the image to see a full-size version of the graph) (Landers et al., P/ACE Setter Newsletter, Vol. 3 Issue 4, December 1999).
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