SNPs have been used as molecular markers in many studies of complex diseases owing to their high frequency and simple variation pattern.These complex diseases (such as cancers, diabetes, autoimmune diseases, and Alzheimers disease) are believed to involve a large number of genetic susceptibility variants, which exert a combined effect to cause disease.The success of such studies can be greatly limited by techniical aspects of SNP genotyping, specifically accuracy, cost-effectiveness, and throughput.Herein, we will present our novel DNA sequencing technology and SNP genotyping techniques as well as their principles of genotype determination.