A DNA database is a centralized collection of DNA profiles, unique genetic patterns used for identification. These databases have become significant tools in forensic science, used for comparisons between DNA found at crime scenes and profiles of individuals. This article explores the historical origins and development of these databases, when and why they began to be established.
The Dawn of DNA Fingerprinting
The foundation for DNA databases was laid in 1984 with the discovery of DNA fingerprinting by British geneticist Sir Alec Jeffreys at the University of Leicester. This breakthrough revealed that specific regions of human DNA exhibit unique patterns for each individual, with the exception of identical twins, making individual identification possible. Jeffreys’ method was first applied in 1985 to resolve an immigration case, confirming family relationships.
The forensic potential of DNA fingerprinting was demonstrated in the Colin Pitchfork case in the UK. DNA evidence was used to exonerate an initial suspect, Richard Buckland, in 1986, marking the first time DNA cleared an innocent person. Subsequently, a mass screening effort led to the identification and conviction of Colin Pitchfork in 1988 for the murders of two teenage girls. This early success highlighted the utility of DNA for identification in criminal investigations, sparking interest in collecting genetic profiles.
Establishing the First National Databases
Centralized DNA profile collection led to the establishment of the first national DNA databases in the mid-1990s. The United Kingdom pioneered this development with the creation of the National DNA Database (NDNAD) in 1995. The Criminal Justice and Public Order Act 1994 provided its legal framework, allowing police to collect DNA samples from individuals charged with recordable offenses. Initially focused on violent and sexual offenses and domestic burglary, the NDNAD rapidly expanded its scope.
In parallel, the United States developed its own national system, the Combined DNA Index System (CODIS), which began as a pilot project in 1990. The National DNA Index System (NDIS), the national level of CODIS, became operational in 1998. The DNA Identification Act of 1994 formalized NDIS’s legal authority, establishing a framework for a national index of DNA records for law enforcement. This legislation also set standards for laboratories contributing profiles to the system.
How Databases Expanded
Following their initial establishment, these national DNA databases grew significantly in scope and size. In the UK, legislative changes in 2001 and 2003 broadened police powers to collect DNA samples, allowing for collection from anyone arrested for a recordable offense, even if they were not subsequently charged or convicted. This expansion led to a substantial increase in the number of profiles stored in the NDNAD, making it one of the largest national forensic DNA databases globally.
Similarly, in the United States, subsequent legislation expanded the CODIS database. The Justice for All Act of 2004 and the Violence Against Women Act of 2005 expanded the types of individuals from whom DNA profiles could be collected, including arrestees, not just convicted offenders. Many US states also changed their laws to permit DNA collection prior to conviction for various offenses. Technological advancements, such as the widespread adoption of Short Tandem Repeat (STR) analysis, also facilitated this expansion.
The Core Purpose of DNA Databases
From their inception, DNA databases were developed to enhance criminal investigations and public safety. A primary purpose was to link biological evidence found at crime scenes to known offenders, often referred to as “offender-crime scene hits”. This capability allows law enforcement to identify potential suspects who may have previously committed offenses.
Additionally, these databases aimed to connect unsolved crime scenes to each other through “crime scene-crime scene hits,” revealing patterns of serial offending even without an immediate suspect. The databases also serve to identify unknown human remains, providing closure for families and assisting in missing persons investigations. Ultimately, the creation and expansion of DNA databases provide an efficient tool for solving crimes and deterring repeat offenders.