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Pre-Extraction Separation of Mixed Source DNA Samples Through Micromanipulation and Direct PCR Short Tandem Repeat Typing of Cells

NCJ Number
Date Published
April 2016
79 pages
This study addressed the challenge of interpreting admixed STR profiles from multiple donors, particularly when dealing with initially small or trace amounts of cellular items, such as touched objects.

This was done by finding a method to collect single cells and the cellular material of fingerprints, by using instruments appropriate for micromanipulation, by separating samples and processing them independently, and by the examination of protocols to extract DNA and amplify STR loci to generate database-eligible profiles. In a discussion of future research on this issue, the study notes that although this study analyzed an enormous number of fingerprints, other laboratories could confirm the outcomes generated by the current study. This would assist in developing a more standardized protocol for handling fingerprints in forensic casework. Validating the Axiozoom for forensic casework could also be beneficial, since this instrument can be used on a variety of criminal cases in which mixed samples of two or more contributors are identified. 19 figures, 2 tables, and 61 references

Date Published: April 1, 2016