- Course Introduction
- 01: Evidence & DNA
- 02: Forensic Biology
- 03: DNA Extraction & Quantitation
- 04: DNA Amplification
- Overview
- Introduction
- Amplification
- Primer Design
- Primer Length
- Primer Melting Temperature
- Primer Annealing Temperature
- Values for Tm
- Maximum 3′ Stability
- GC Content Percentage
- No Secondary Structures
- No Self-complementarity
- No Complementarity To Other Primers
- No Long Runs With The Same Base
- Distance Between Two Primers On Target Sequence
- Plateau Effect
- Thermal Cyclers
- Thermal Cycling Parameter and Optimization
- Works Cited & Online Links
- Locus Selection
- Multiplexing
- Contamination
- Overview
- 05: Amplified DNA Product Separation
- 06: STR Data Analysis & Interpretation
- 07: Population Genetics & Statistics
- 08: Communicating Results
- 09: Other DNA Markers & Technologies
- Course Resources
- Laboratory Training Manual
President's DNA Initiative
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Advancing Justice Through DNA Technology
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Advancing Justice Through DNA Technology
DNA Analyst Training
Overview
Home > DNA Amplification > Locus Selection > Overview
In the United States, the Federal Bureau of Investigation (FBI) bears the responsibility for maintenance of the national DNA database. The FBI worked with the relevant scientific communities to identify appropriate markers for STR DNA analysis. The European Network of Forensic Science Institutes (ENFSI) performed a similar role in Europe.
Click here to visit the FBI's Laboratory Services website.
Click here to visit ENFSI's website.
The steps involved in the selection of loci are:
- Identify loci that have been published and characterized and are not linked (see Subject 07, Module 01, Population Theory)
- Select the best candidates for use in forensic science.
- Run numerous population database samples to establish discriminating power (see Subject 02, Module 02, Testing of Bodily Fluids and Tissues) and population frequency data.
- Conduct method development (e.g. multiplex kits).
- Conduct validation studies.
The selection of a core set of loci by the forensic science community must include consideration of method development. Multiplex systems are complex, and while certain loci may be more desirable than others, loci are selected based on their suitability in a multiplex system and their discriminating power.
Currently, a few manufacturers develop STR multiplex kits for mainstream forensic science use. Historically, the manufacturers and the forensic science community have collaborated to develop suitable end products. This has greatly benefited the forensic science community because it is unlikely that these laboratories would be able to devote the resources required for multiplex method development.
