The detection of single-base change mutations and polymorphisms is of enormous importance, both in research and in diagnostics. The ability to identify and score single nucleotide polymorphisms (SNPs) is becoming a key element of gene identification and mapping, and the future of human diagnostics depends on having the ability to detect single-base change mutations, because these represent the vast majority of disease-causing and diseaseassociated mutations. An ideal system for detecting and scoring these mutations and SNPs will have certain key characteristics: (1) robustness: the method will be user friendly and not subject to wide fluctuations caused by small changes in experimental conditions; (2) high throughput: given the requirements of genomic research and large-scale diagnostics, a useful method of mutation/SNP detection must be able to handle thousands of samples per day with limited technician effort; (3) low cost: for wide-spread use in both research and clinical diagnostics, low-cost and easy availability of both equipment and reagents is crucial; (4) no gels: this requirement is primarily to meet the high throughput requirement; (5) no radioactivity: given the problems of radioactive material handling and disposal and the availability of a wide variety of alternatives, radioactivity should not be a part of the ideal mutation detection system. Although there may be additional preferences of individual researchers, any mutation/SNP detection system that successfully