New laws are increasing DNA caseloads, but recent and upcoming technology is helping to close the gap and improve the quality of forensic DNA testing and analysis.

Over the past fifteen years numerous scientific improvements have advanced the field of forensic DNA testing, significantly altering the way evidence is processed and greatly enhancing its role within the criminal justice system. The utilization of PCR based methods has progressed from D1S80 amplified fragment length polymorphism analysis and DQA1 & Polymarker Reverse Dot Blot Hybridization assays to today’s highly discriminatory multiplex STR systems. These technological advances now enable increasing amounts of genetic information to be obtained from limited quantities of a wide variety of extremely challenging samples that previously yielded little or no results, leading to a greater reliance on, and demand for, DNA testing in criminal cases. The proven success of leveraging DNA during the investigative process has driven the passage of new legislation, increased sharing of DNA information between countries, and initiated a rigorous evaluation of the use of DNA for a larger number and wider variety of criminal cases. Investigators now routinely rely on the results of forensic DNA analysis and have a greater understanding of its impact on their cold and active cases. As a result, there is a growing expectation among investigators and attorneys that the scientific limitations of DNA testing will continue to dissolve and that more cases will be resolved using DNA testing.

In response to the increased demand for DNA analysis, laboratories are continuously implementing improved methods that allow them to process database and casework samples more efficiently. Recent advances, including automatable extraction methodologies, the availability of a predictive dual quantitation assay that allows assessment of the potential probative value and performance of a sample in downstream analyses, the development of next generation STR multiplexes and mini-STR kits¹ that improve performance on degraded and compromised samples, and expert system analysis software,² all combine to provide DNA analysts with an expanded set of capabilities in their forensic “tool-box.” These tools better equip them to meet the needs of law enforcement and provide results that enhance their database and casework analysis while speeding up the overall process.

Technology Advances Promise a Bright Future
The success of DNA typing has affected more than the workflow of evidentiary samples within the crime laboratory. Historical data clearly illustrates the power of DNA to identify perpetrators and link suspects to multiple crimes, and recent findings by the Urban Institute suggest that DNA is more effective than traditional investigative tools across the judicial-legal system for investigating crime scenes and prosecuting suspects.³ Additional studies have quantified the cost savings realized by agencies that use DNA as an investigative and not merely a prosecutorial tool.⁴ These studies support the rationale behind increased requests for DNA testing made by law enforcement, prosecutors, and even the public, and are responsible for the creation of a global trend to use DNA in investigations of a broader range of crimes. This is reflected by policy makers throughout the world continuing to pass legislation that requires the collection and analysis of expanded offender and suspect samples. And, while additional legislative mandates have proven valuable for society, an ever increasing burden has been placed on crime laboratories to constantly evaluate and implement new methods while simultaneously managing growing caseloads. Laboratories are still searching out new ways to meet these challenges. Although the technologies discussed below will require validation by the laboratory, they promise to dramatically impact sample management and workflow by completely eliminating steps, further reducing analysis time, and offering alternative technologies that recover even more genetic information.