Universal Tag Arrays in Forensic SNP Analysis

Microarray-based single nucleotide polymorphism (SNP) genotyping enables simultaneous and rapid detection of a large number of markers and is thus an attractive method for forensic individual acid identification. This assay relies on a one-color detection system and minisequencing in solution before hybridization to universal tag arrays. The minisequencing reaction is based on incorporation of a fluorescent dideoxynucleotide to a primer containing a tag-sequence flanking the position to be interrogated. This one-color system detects C and T polymorphisms in separate reactions on multiple polymerase chain reaction targets with the fluorophore TAMRA coupled to the respective dideoxynucleotide. After incorporation, tagged primer sequences are hybridized through their complementary sequence on the array, and positive signals are detected by a confocal laser-scanner.