Single nucleotide polymorphism analysis using a bacterial magnetic particle microarray

An approach to analyzing single nucleotide polymorphism (SNP) found in the human genome has been developed using a bacterial magnetic particle (BMP) microarray. Streptavidin was bound to BMPs using biotin labeled cross-linkers reacting with the amine group on BMPs. PCR was performed using TRITC and biotin labeled primer pairs for amplification of ALDH2 fragment. PCR products were conjugated with BMPs by the interactions of biotin-streptavidin. DNA-BMP complexes were spotted on a slide-glass, immobilized magnetically then treated with a restriction enzyme specifically digesting the wild-type sequences (normal allele of ALDH2). The homozygous (ALDH2*1/*1), heterozygous (ALDH2*1/*2), and mutant (ALDH2*2/*2) genotypes were successfully discriminated by imaging the BMP microarray before and after digestion and measuring spot fluorescence intensities on the slide glass.