Multiplex SSCP and heteroduplex analysis with Southern hybridization for large-scale mutation detection

We have developed a modification of the single-strand conformational analysis and heteroduplex analysis methods of mutation detection, with the intention of applying them to genetic diseases involving large genes or multiple genes producing a similar phenotype. The technique involves electrophoresing up to 10 or more DNA fragments on a polyacrylamide gel, followed by bidirectional Southern blotting and individual examination by hybridization. This can reduce the time involved in mutation detection by more than 50%. We confirmed the validity of our approach by detecting 90% of mutations in a blind study of previously characterized mutations in the adenomatous polyposis coli (APC) gene that underlies familial adenomatous polyposis.