A novel simple fluorescent method for the discrimination of single-nucleotide polymorphisms( SNPs) was developed. Three molecular logic gates were designed by utilizing four mutations of SNPs( target-A,target-T,target-C and target-G) as the inputs and the fluorescent intensities of small fluorescent molecules including 2-amino-7-methyl-1,8-naphthyridine as the outputs. The threshold was defined and obtained from the relative fluorescent intensities. The experiment results showed that the discriminate SNPs g...