PCR-VNTRs (PCR-Variable Number of Tandem Repeats) in forensic science

PCR-VNTRs are important markers for the individualization in forensic science. Before their use in routine case work extensive validation studies such as population genetics, mutation rates and experimental sensitivity studies have to be carried out. Different applications of PCR-VNTRs in stain analysis, even with difficult stain material such as hair shafts and only a few sperm cells are demonstrated. The different extent of sequence heterogeneity in STR systems was verified by Taq-cycle-sequencing. STRs can be divided into systems with a constant (HumTH01), variable (HumVWA) and highly variable (HumACTBP2) sequence structure. As a consequence some STR systems are not only characterized by their length polymorphism, but also by a highly variable sequence polymorphism.