ABSTRACT
While looking ahead to the development of new, disruptive technologies that will change the face of forensic DNA analysis, it is interesting to look back at some of the critical developments that provided the underpinning for them. e early 1970s and 1980s were rampant with advances in biochemistry that provided the framework for modern molecular techniques. In 1975, O’Farrell described 2D gel electrophoresis and revolutionized our ability to interrogate the proteinaceous components of cells by exploiting a separation method that provided unprecedented resolution of proteins (O’Farrell 1975). e year 1985 brought new capabilities to the nucleic acids eld in the form of two inuential papers that seeded paradigm-shiing technologies that would change the face of human identication (HID) analysis. In March 1985, Professor (now Sir) Alec Jereys reported the discovery of “minisatellite” regions in the human genome that could be used as a tool to identify molecular dierences between individuals (Jereys et al. 1985). He demonstrated that these minisatellites repeat throughout the genome and that the number of repeats varied from person to person, hence, variable number of tandem repeats (VNTR). Using restriction enzymes, Dr. Jereys was able to show the dierences in the length of each fragment caused by the dierences in the number of repeats; this technique is known as restriction fragment length polymorphism (RFLP). In December of the same year, Dr. Kary Mullis reported the amplication of target DNA regions using the polymerase chain reaction (PCR) (Saiki et al. 1985). By using primers with sequences specic to a target region and temperaturecycling a sample through three temperatures in the presence of a polymerase, as well as dNTPs, the target region can be exponentially amplied in copy number. Although it took half a decade before these two methods would be conjoined to yield an unparalleled force for human identication, the groundwork for modern DNA analysis had been laid. For reasons that are obvious, all three of these are citation classics (exceeding 400 citations).
