Training Guidelines by Scientific Working Group on DNA Analysis Methods (SWGDAM) (Forensic Science Communications, October 2001)
October 2002 - Volume 4 - Number 4
Standards and Guidelines
Scientific Working Group on DNA Analysis Methods (SWGDAM)
January 23, 2001
The FBI Director issued Quality Assurance Standards for Forensic DNA Testing Laboratories (effective October 1998) and Quality Assurance Standards for Convicted Offender DNA Databasing Laboratories (effective April 1999) that include requirements for four categories of laboratory personnel involved in forensic DNA analysis. Because of the issuance of those standards, the specific course requirements, in-house laboratory training and assessment, and minimal experience needed for examiners/analysts before assuming responsibility for casework samples needed to be defined. The Scientific Working Group on DNA Analysis Methods (SWGDAM) addressed these issues and prepared guidelines for training new personnel in forensic laboratories performing DNA analysis. These guidelines are based on the FBI Director's standards and input from members of SWGDAM and the forensic community. The guidelines are intended to assist forensic laboratories in training and determining budget resources.
The primary emphasis of the guidelines is to provide a model program of standardized study and training for laboratory personnel throughout the forensic DNA community. The benefits of these guidelines include improving the overall quality of work in private and public forensic laboratories performing forensic DNA analysis and allowing for greater flexibility and confidence in hiring laboratory staff. An ancillary benefit is guiding universities and forensic laboratories in developing and implementing educational and practical experiences common to all analysts.
This document should assist laboratory directors in developing a training program applicable to the analytical methods used by their laboratories. Suggestions and directions are given to those involved in curriculum development in forensic science and related course work. Laboratory directors should consider including the aspects of these guidelines in their training programs when performing their annual reviews. These are guidelines and should be expanded and tailored to each laboratory and its training requirements.
The training program employs a module system, and successful completion of each module is the goal of the trainee. This program is developed for the new employee (or a current employee new to DNA analysis). An examiner/analyst with prior training in forensic or other DNA analysis may not require all modules or steps. Similarly, the module content may be tailored as applicable to various job descriptions including technicians and reporting scientists. The module content should be customized to include all aspects of procedures and policies of the training laboratory. The laboratory should retain all documentation of the trainee's work. In accordance with the FBI Director's Quality Assurance Standards, a training program should take a new examiner/analyst a minimum of six months.
The laboratory should develop the following to track the training program:
- Forms that track the completion of the specified tasks in Modules 1, 2, and 4 through 7.
- Written and/or oral examinations that cover the range of topics specified by the defined tasks. A copy of the examination questions and documentation of the trainer's evaluation of the trainee's response to those questions will be maintained.
An introduction to the laboratory and the training program should be developed and provided. Upon completion, the trainee shall be familiar with the general operation of the forensic laboratory and the expectations of the training program.
1.2.1. Instruction for the trainer and the trainee
1.2.2. Orientation to the laboratory facility
1.2.3. Instruction on the organizational structure, code of ethics, and chain of command
1.2.4. Instruction on the security and confidentiality issues of a forensic laboratory
1.2.5. Introduction to the quality control/quality assurance program including documentation
126.96.36.199. Chemical hygiene plan
188.8.131.52. Fire safety
184.108.40.206. Bloodborne pathogens procedures
220.127.116.11. Material Safety Data Sheets
18.104.22.168. Laboratory policy on incident reports
22.214.171.124. Radiation training (where applicable)
126.96.36.199. Decontamination procedures
1.3. Reading Assignments
1.3.1. Quality control/quality assurance manual
1.3.2. Administration manual and operations manual
1.3.3. TWGDAM Guidelines (1989, 1991, 1995)
1.3.4. Quality Assurance Standards for Forensic DNA Testing Laboratories (2000) and/or Quality Assurance Standards for Convicted Offender DNA Databasing Laboratories (2000)
1.4.1. Module should be completed by examiners/analysts, technicians, and laboratory support personnel.
1.4.2. Documentation of successful completion of each task by form
To instruct the trainee on evidence handling in the forensic laboratory.
2.2.1. Instruction on the following topics:
188.8.131.52. Sample collection, packaging, and storage
184.108.40.206. Chain of custody, receiving, and handling evidence
220.127.116.11. Contamination of evidence
18.104.22.168. Case acceptance policy
22.214.171.124. Consumption of evidence
126.96.36.199. Laboratory documentation policy including paper or electronic case files
2.3. Reading Assignments
2.3.1. Laboratory evidence-handling protocol
2.4.1. Module should be completed by examiners/analysts and technicians.
2.4.2. Documentation of successful completion of each task by form
To ensure that a trainee has or is provided the formal education and the working knowledge of the fundamental scientific bases of forensic DNA analysis.
3.2.1. Laboratory analysts must have documentation of college-level course work covering fundamental and applied principles of genetics, biochemistry, and molecular biology as applied to forensic DNA analysis. Whereas there is considerable overlap in these fields, each has unique perspectives. Genetics refers to the study of inherited traits, genotype/phenotype relationships, and population/species differences in allele and genotype frequencies. Biochemistry covers the nature of biologically important molecules in living systems, DNA replication and protein synthesis, and the quantitative and qualitative aspects of cellular metabolism. Molecular biology covers theories, methods, and techniques used in the study and analysis of gene structure, organization, and function. Specific syllabus topics are not included because of variation in course titles, content, or curriculum emphasis. It is likely that more than one course will be necessary to adequately educate the trainee in these areas.
3.3. Reading Assignments
3.3.1. Committee on DNA Forensic Science, National Research Council (1992) DNA Technology in Forensic Science, Chapters 2, 4, 5, 6, and 7
3.3.2. Committee on DNA Forensic Science, National Research Council (1996) The Evaluation of Forensic DNA Evidence
3.4.1. Module should be completed by examiners/analysts.
3.4.2. Documentation of a trainee's successful completion of these tasks should be assessed by review of college transcripts and, if necessary, review of course descriptions or syllabi. Trainee must pass a written or oral qualifying test that assesses understanding of fundamental scientific knowledge as it applies to forensic DNA analysis.
To educate the trainee on the specific knowledge related to the field of forensic DNA analysis. The level of detail should be applicable to the trainee's job description.
4.2.1. Provide in-depth theoretical instruction on each topic appropriate to work being conducted in the laboratory and basic theoretical knowledge on any remaining topics.
188.8.131.52. Southern Blot Analysis/Restriction Fragment Length Polymorphisms (RFLP)
184.108.40.206. Polymerase Chain Reaction (PCR)-based methods
220.127.116.11. Polymarker (PM) + DQA1
18.104.22.168. Short Tandem Repeats (STR)
22.214.171.124. Mitochondrial DNA
126.96.36.199. Relevant population genetics and forensic statistics
4.3. Reading Assignments
4.3.1. Laboratory's validation data
4.4.1. Module should be completed by examiners/analysts and technicians.
4.4.2. Documentation of successful completion by written and/or oral examination
To provide practical instruction to the trainee on analytical procedures used in the laboratory.
5.2.1. The laboratory should provide instruction, training, and practice on the following topics as they relate to the laboratory's standard analytical procedures:
188.8.131.52. DNA quantization
184.108.40.206. Southern Blot Analysis/RFLP
220.127.116.11. PCR-based methods
18.104.22.168. PM + DQA1
22.214.171.124. Mitochondrial DNA
5.3. Reading Assignments
5.3.1. Laboratory's analytical protocols
5.3.2. Kit manufacturer's literature
5.4.1. Module should be completed by examiners/analysts and technicians.
5.5. A new DNA laboratory trainee must complete a training notebook documenting his/her own experiences performing evidentiary or known sample analysis. The type of samples included must vary, reflecting the range, type, and complexity of casework or database analyses routinely handled by his/her laboratory duties. To assist in ensuring basic competency, this training notebook must document analysis of a minimum of 50 samples for nuclear DNA analysis. A trainee performing mitochondrial DNA analysis will test an adequate number of samples to ensure a minimum of 50 successful amplifications. No more than 1/3 of these 50 samples can be from one evidentiary or known sample type, unless the trainee only performs analysis of a single sample type (e.g., database analyst).
To learn how to interpret and report analytical results according to the laboratory's policy.
6.2.1. The trainee should receive instruction on the following:
126.96.36.199. Laboratory interpretation guidelines including interpretation of mixtures
188.8.131.52. Laboratory policy on case-jacket content
184.108.40.206. Statistical calculations
220.127.116.11. Report writing
6.3. Reading Assignments
6.3.1. Laboratory interpretation guidelines
6.4.1. Module should be completed by examiners/analysts.
6.4.2. The trainee will review 20 sets of data representative of casework and provide a written interpretation of the data according to the laboratory policy. The trainer will review and assess the reports for accuracy. These data sets can be samples representative of typical casework or actual casework data. The laboratory can maintain a standard file of data sets or share sets with other laboratories.
To instruct the trainee on the legal system of his/her own jurisdiction.
7.2.1. The trainee should receive instruction on the following topics:
18.104.22.168. Courtroom procedures and rules of evidence
22.214.171.124. Examiner/analyst qualifications
126.96.36.199. Technical testimony
188.8.131.52. Courtroom demeanor and attire
184.108.40.206. Testimony practice
220.127.116.11. Moot court(s)
18.104.22.168. Discovery and admissibility rules
22.214.171.124. Ethical responsibility of expert witness
126.96.36.199. Court system structure
188.8.131.52. Evidence presentation
7.2.2.The examiner/analyst will prepare a curriculum vitae and observe expert testimony.
7.3. Reading Assignments
7.3.1. Relevant and appropriate transcripts or pertinent case law
7.4.1. Module should be completed by examiners/analysts.
7.4.2. Completion of this module should be demonstrated by a minimum of one successful moot court. Documentation of the moot court should contain an evaluation of the trainee's performance and be retained by the laboratory.
8.1. At the completion of this program, the trainee will successfully pass a qualifying test relevant to his/her job description. This test will represent a mock case using samples representative of the samples the trainee will be analyzing on the job. The trainee will prepare full documentation of the analysis in the form of the laboratory's standard case jacket.
SWGDAM Training Guidelines require that the technical leader and the examiner/analyst receive and complete the reading of a list of references specific to issues in forensic DNA. This list must include primary source material from scientific journals on each of the following topics:
- Forensic applications of genetic polymorphisms
- Restriction Fragment Length Polymorphism (RFLP)
- Amplified Length Polymorphism (AmpFLP)
- Short Tandem Repeats (STR)
- Mitochondrial DNA
- PCR applications
- Population statistics
- Paternity and nonhuman applications
The following bibliography represents a sample list of resources that may be helpful to the trainer in defining the breadth and scope of the materials for the trainee's reading. This list is not meant to be all inclusive. The laboratory should develop a list tailored to its specific needs.
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Budowle, B. and Baechtel, F. S. Modifications to improve the effectiveness of restriction fragment length polymorphism typing, Applied Theoretical Electrophoresis (1990) 1(4):181–187.
Budowle, B., Chakraborty, R., Giusti, A. M., Eisenberg, A. J., and Allen, R. C. Analysis of the VNTR locus D1S80 by the PCR followed by high-resolution, American Journal of Human Genetics (1991) 48(1):137–144.
Budowle, B., Giusti, A. M., Waye, J. S., Baechtel, F. S., Fourney, R. M., Adams, D. E., Presley, L. A., Deadman, H. A., and Monson, K. L. Fixed-bin analysis for statistical evaluation of continuous distributions of allelic data from VNTR loci for use in forensic comparisons, American Journal of Human Genetics (1991) 48(5):841–855.
Budowle, B., Koons, B. W., and Moretti, T. R. Subtyping of the HLA-DQA1 locus and independence testing with PM and STR/VNTR loci, Journal of Forensic Sciences (1998) 43(3):657-660. Erratum, Journal of Forensic Sciences (1998) 43(5):1105.
Budowle, B., Lindsey, J. A., DeCou, J. A., Koons, B. W., Giusti, A. M., and Comey, C. T. Validation and population studies of the loci LDLR, GYPA, HBGG, D7S8, and Gc (PM loci), and HLA-DQ alpha using a multiplex amplification and typing procedure, Journal of Forensic Sciences (1995) 40(1):45–54.
Budowle, B., Monson, K. L., Giusti, A. M., and Brown, B. L. The assessment of frequency estimates of Hae III-generated VNTR profiles in various reference databases, Journal of Forensic Sciences (1994) 39(2):319–352.
Budowle, B., Moretti, T. R., Keys, K. M., Koons, B. W., and Smerick, J. B. Validation studies of the CTT STR multiplex system, Journal of Forensic Sciences (1997) 42(4):701–707.
Budowle, B., Smerick, J. B., Keys, K. M., and Moretti, T. R. United States population data on the multiplex short tandem repeat loci--HUMTHO1, TPOX, and CSF1PO and the variable number tandem repeat locus D1S80, Journal of Forensic Sciences (1997) 42(5):846-849. Erratum, Journal of Forensic Sciences (1998) 43(1):253.
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Budowle, B., Wilson, M. R., and DiZinno, J. A. Mitochondrial DNA regions HVI and HVII population data, Forensic Science International (1999) 103:23–35.
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Committee on DNA Forensic Science, National Research Council. DNA Technology in Forensic Science. National Academy Press, Washington, DC, 1992.
Committee on DNA Forensic Science, National Research Council. An Update: The Evaluation of Forensic DNA Evidence. National Academy Press, Washington, DC, 1996.
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