Southern Blotting of Genomic DNA for DNA Profiling

The investigation of DNA polymorphisms has revolutionized forensic-identity analysis over the past decade. Since the first papers by Jeffreys on “DNA fingerprinting” appeared in 1985, DNA-based profiling techniques have been adopted by the worldwide forensic community. Until very recently, the primary method for DNA analysis was the detection of restriction fragment-length polymorphisms (RFLPs) generated at a number of highly polymorphic loci. These loci are characterized by the presence of variable numbers of tandemly repeated conserved DNA sequences (and are hence termed VNTR loci). The RFLPs are detected by hybridization of Southern blots of total genomic DNA with a probe homologous to the conserved repeated sequence.