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The Evolution of Forensic DNA Laboratories and The Challenges They Face

Sun, 04/01/2007 - 4:00am
Lisa Lane Schade, MHRLisa CalandroDennis J. Reeder

DNA laboratories have come a long way but challenges still exist.

Before 1990, the majority of U.S. forensic laboratories were associated with law enforcement agencies, yet received a relatively small portion of their given agency’s total budget. In general, laboratories performed a range of services including drug testing, firearm examinations, bullet comparisons, paint chip characteristics, assessment of tool marks, serology, handwriting analysis, and fingerprint comparisons. Laboratory personnel received training in fingerprints, basic and advanced blood stain and bullet pattern analysis, evidence collection, and crime scene processing. Due to the length of time and high cost required to obtain probative information, large numbers of samples were not processed.

Law enforcement relied upon forensic laboratories to provide a basic level of discrimination of biological evidence. Analyses of this evidence in cases involving intimate contact were conducted using serological tests such as ABO blood typing and analysis of polymorphic isoenzymes such as Esterase D to enhance the power of discrimination. Discrimination of protein markers was achieved largely through immunological methods or electrophoretic methods using starch gels or isoelectric focusing plates. Phenotyping of biological evidence was possible but required technical expertise and was subject to certain limitations such as the need for fresh semen samples in the analysis of sexual assault evidence. Overall, the typing methods in use provided limited discrimination and lacked the capability to individualize biological evidence. In some cases, individuals who could not be excluded on the basis of serological analysiswere exonerated years later through DNA testing.

In 1988, the Technical Working Group on DNA Analysis Methods (TWGDAM) was established at the Federal Bureau of Investigation in Quantico, Virginia. The success of TWGDAM manifested itself in the publication of quality assurance guidelines for DNA testing1and raised the bar not only for DNA analysis, but for all forensic disciplines. As the technology matured, the group was renamed SWGDAM, or Scientific Working Group on DNA Analysis Methods, and the concept of the Scientific Working Group (SWG) became formalized. To improve the scientific standards of each of the forensic disciplines, new groups were established to address specific quality assurance needs and set forth guidelines for bestpractices (Figure 1).

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Figure 1. Scientific Working Groups for forensic disciplines.

FOLLOWING QUALITY ASSURANCE STANDARDS
In 1995, the DNA Advisory Board (DAB) was formed by congressional mandate under the DNA Identification Act of 1994 as a separate and distinct advisory board administered by the Federal Bureau of Investigation. Initial goals of the DAB were to establish quality standards for forensic DNA testing laboratories and convicted offender DNA databasing laboratories as well as make recommendations as to the feasibility of blind proficiency testing. Using the TWGDAM/SWGDAM guidelines, along with input from a variety of forensic and standards organizations, the DNA Advisory Board presented The Quality Assurance Standards for Forensic DNA Testing Laboratories2 to the Director of the FBI. These standards were approved on July 15, 1998, and took effect on October 1, 1998. This was followed by The Quality Assurance Standards for Convicted Offender DNA DatabasingLaboratories3which took effect on April 1, 1999.

In the Quality Assurance Standards, a quality system was outlined in Standard 3.1 that states, “The laboratory shall establish and maintain a documented quality system that is appropriate to the testing activities. The quality manual shall address at a minimum: (a) goals and objectives; (b) organization and management; (c) personnel qualifications and training; (d) facilities; (e) evidence control; (f) validation; (g) analytical procedures; (h) calibration and maintenance; (i) proficiency testing; (j) corrective action; (k) reports;(l) review; (m) safety; and (n) audits.”

Strict adherence to these quality assurance standards requires a commitment of time, resources, and personnel imposing daily challenges on every forensic DNA laboratory.

PROCESSING MORE SAMPLES WHILE FACING PERSONNEL SHORTAGES
With the burgeoning demand for increased throughput and analysis capacity, as well as the need for elimination of casework backlogs, there is an ever-increasing need to work more efficiently. In addition, the ability to hire and retain laboratory staff is limited. According to a 2004 study published by W. Mark Dale and Wendy Becker,4 a number of factors related to personnel issues can impact laboratory productivity. Laboratories must secure funds for hiring in a competitive biotechnology environment, devote the resources of experienced staff to training newly-hired personnel, and provide incentives to reduceturnover.

Pressures on laboratory management to streamline their operations while maintaining quality practices and analysts require technical leaders to evaluate other means of increasing laboratory efficiency. Awareness of new technologies and the availability of financial assistance are necessary to enable laboratory managers to obtain equipment and materials. Such resources improve the ability to conduct the basic processes of DNA analysis (extraction, quantification, amplification, capillary electrophoresis, and data analysis) while reducing hands-on labor requirements, thereby increasing sample throughput with minimal addition of personnel.

VALIDATION SOFTWARE TO STREAMLINE THE VALIDATION PROCESS

Validation involves performing laboratory tests to verify that a particular instrument, software program, or measurement technique is working properly.

Without validation studies, laboratories cannot be confident in results produced by a new genetic test, instrument, or software program. These studies help define range and relevance of measurements made with a method.

Emerging validation software is designed to provide a series of integrated tools to effectively define, execute, and manage validation from start to final report.

• It integrates all validation workflow processes, including the initial experimental design, PCR setup, amplification, post-PCR set-up, data analysis of validation experiments, statistical analysis, and final reporting.

• It automates worksheet generation and imports setup files for quantification, normalization, dilution/mixture preparation, amplification, capillary electrophoresis, and genotyping.

• Specific data analysis and graphing tools help identify optimal operating parameters and performance characteristics required to establish standard operating procedures and interpretation guidelines.

• Its project and documentation management capabilities enable laboratories to track validation progress and maintain validation-associated information for accreditation, training, and/or auditing purposes.

An example of this type of validation software is VALID Software from Applied Biosystems.

 

EXPANDED FUNDING HELPS LABORATORIES FACE CHALLENGES
Recognizing that the challenges faced by forensic DNA laboratories were significantly impacting the effectiveness of DNA as a criminal justice tool, the federal government commissioned a group of experts to review the issues. According to Chris Asplen, Vice President of Gordon Thomas Honeywell Governmental Affairs and a former member of this commission, “The number of post-conviction exonerations indicated that the potential of DNA technology was not being realized. However, the backlog of DNA cases waiting to be analyzed (up tofour years) clearly reflected a system incapable of absorbing greater utilization of the technology.” As a result, recommendations for expanded funding were made. The Debbie Smith or “Justice for All” Act passed on November 1, 2004, led to increased funding to improve the use of DNA in the criminal justice system. President Bush proposed $232.6 million in federal funding in fiscal year 2004 for his initiative, Advancing Justice Through DNA Technology, and called for continuing this level of funding for five years – a total commitment of over $1 billion.5 The initiative called for increased funding, training, and assistance for Federal, State, and local forensic laboratories, as well as police, medical professionals, victim service providers, prosecutors, defense lawyers, and judges in order to ensure that DNA technology reaches its full potential to solve crimes, protect the innocent, and identify missing  persons.

“The work completed in prior years studying vast potential as well as the existing shortfalls of forensic DNA testing led Congress to create a very comprehensive program to make sure our laboratories could increase their capacities to meet both current and, hopefully, future demand and challenges,” said Lisa Hurst, manager of DNAresource.com. Funding is available to enable laboratories to enhance basic infrastructure through automation and computerization, improvements in forensic evidence storage systems, and recruitment of additional personnel to help process increased sample numbers. Funds are also available to upgrade, replace, and purchase laboratory equipment, instrumentation, and computer hardware and software including LIMS for forensic data management. In order to enable laboratories to implement new technologies, funding is available for suppliesand expenses directly attributable to validation.

FORENSIC DNA LABORATORIES CONSIDER TECHNOLOGY OPTIONS
Although the availability of funding can help laboratories address the challenges they face, in order to make the best use of this funding, laboratories should consider their specific needs and managers should be aware of technology improvements that consolidate and streamline their workflow. To achieve this many laboratories have participated in a series of workshops to enhance their planning and develop a clear understanding of future needs. Several organizations offer “process mapping” services (see Forensic Magazine®April/May 2006)6 which help to identify the need for facility design improvements, additional equipment, laboratory workflow enhancements, and additional personnel. Process mapping may also reveal gaps in testing processes and areas where small adjustments may result in great improvements to laboratory efficiency.

Once a laboratory has identified where improvements in workflow can be made, a variety of tools can be implemented to achieve this. For example, significant advancements in information technology provide laboratories with case management and chain of custody tools, bench top systems integrating instrumentation and robotics, and streamlined methods of data analysis and case reporting.

Additional resources are available to assist laboratories in the validation of new technologies such as the outsourcing of validation services and the development of a new software package (available in summer 2007 from Applied Biosystems). These resources guide laboratories through the validation process in an expeditious manner facilitating experimental design, data analysis, and data management. Although forensic scientists face many challenges, laboratories have met them with innovative thinking, improved science, and a better understanding of their workflow and needs. Exciting developments are on the horizon that will increase sample throughput at a lower cost while requiring less personnel resources. The ability of law enforcement to maximize the use of DNA in every case to provide investigative leads promises to facilitate the swift resolution of criminal cases and the identification of the missing.

References

  1. TWGDAM Guidelines for a Quality Assurance Program for DNA Analysis, Crime Laboratory Digest (1991) 18:44-75
  2. Quality Assurance Standards for Forensic DNA Testing Laboratories, Forensic Science Communications, July 2000, Volume 2, Number 3, available at: http://www.fbi.gov/hq/lab/fsc/backissu/ july2000/codis2a.htm
  3. Quality Assurance Standards for Convicted Offender DNA Data-basing Laboratories, Forensic Science Communications, July 2000, Volume 2, Number 3, available at:
    http://www.fbi.gov/ hq/lab/fsc/backissu/july2000/codis1a.htm
  4. W.M. Dale and W.S. Becker, A Case Study of Forensic Scientist Turnover, Forensic Science Communications, July 2004, Vol. 6, Number 3.
  5. http://www.whitehouse.gov/infocus/justice/dna_initiative_ policy_book.pdf
  6. Ken Mohr and Nancy Sopuch, Most Wanted: Answers to Facility Issues Process Mapping Informs Forensic Laboratory Design, Forensic Magazine, April/May 2006

 

Dennis J. Reeder, Ph.D., is the President of Reeder Analytical Consulting since 2005, having retired from Applied Biosystems in 2005 and the National Institute of Standards and Technology in 2000. Dr. Reeder has a BS degree in Physics and a MS degree in Microbiology from Brigham Young University and his Ph.D. in Immunology and Biochemistry was from the University of North Texas.

Lisa Calandro is the Senior Forensic Scientist and Manager of Technical Marketing in the Human Identification Group at Applied Biosystems. In her role, Lisa leads a team of Forensic Scientists to define user requirements for new Human Identification products and to provide training and support to forensic analysts world-wide. Ms. Calandro received her Bachelors degree in Microbiology and Immunology and her Masters degree in Forensic Science from U.C. Berkeley.

Lisa Lane Schade is responsible for working with forensic DNA laboratories around the world to help define and execute the strategic direction for the Human Identification business at Applied Biosystems. She has a BS in Microbiology with a minor in Chemistry and a Masters degree from the University of Oklahoma, where she served as the Assistant Director of the Advanced Center for Genome Technology. http://info.appliedbiosystems.com/hid 

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