Abstract
DNA profiling has become a standard technique in criminal investigations due to its ability to obtain results from any biological material. PCR-based DNA typing systems have also enabled analyses of DNA obtained from highly decomposed human remains. Based on the length and genomic distribution of the core repeat sequences, two systems are classified as minisatellites and microsatellites (or short tandem repeats). In particular, short tandem repeats (STRs) are abundant classes of polymorphic loci dispersed throughout the entire genome. Each STR locus usually consists of a limited number of the core repeats of 2-5 basepairs, which can easily be resolved by analytical gel electrophoresis. In combination with the use of fluorescence-labelled primers employing different fluorescent dyes, STR loci with overlapping or identical allele size ranges can be analyzed together in the same lane of polyacrylamide gel, thus providing a rapid and accurate method for human identification. Automated DNA profiling by fluorescence-based technology, as well as its application, have been studied and validated for use in forensic laboratory routine.
