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STR Data Analysis and Interpretation for Forensic Analysts


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STR Data Analysis and Interpretation for Forensic Analysts

STR Data Analysis & Interpretation
National Institute of Justice (NIJ) (see reuse policy).

This course provides information in three lessons.

STR (Short Tandem Repeat) Data Analysis and Interpretation Software. Learn the basics of data analysis software, become familiar with the purpose of GeneScan® and Genotyper® software, learn the difference between GeneScan® and Genotyper® software and GeneMapper ID® software, and become aware of the unique features of GeneMapper ID® software, and understand FMBIO® Analysis software and STaRCallTM software as related to GeneScan® and Genotyper® software.

Data Troubleshooting. Learn about commonly used STR data interpretation parameters and thresholds, spurious peaks, pull-up, stutter, microvariants, degradation, stochastic effects, allele dropout, mutations, and controls used in troubleshooting STR data.

Data Interpretation and Allele Calls. Learn the factors that can influence the output from instruments used in DNA analysis, learn about the controls and other techniques used to validate instrument output, compare methods to evaluate data and recognize analysis artifacts, and learn how to analyze data from single source and mixed source samples.

Taking the Course

Starting the course. Select the top link in the navigation on the right.

Navigating the course. We recommend you go through the course page-by-page using the Forward and Back buttons at the bottom of the page. You may skip around and select lessons using the navigation on the right.


Information addressed in this interactive training program is delivered in two modules. Select a module below to begin.

STR Data Analysis and Interpretation Software
Data Troubleshooting
Data Interpretation & Allele Calls