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Development of Improved Insertion-Deletion Assays for Human and Ancestral Identifications From Degraded Samples

NCJ Number
Bobby L. LaRue
Date Published
July 2016
91 pages
The overall purpose of this project was to develop an improved method for typing degraded DNA by demonstrating the utility of small insertions or deletions (INDEL) in the genome and other similar biallelic markers that may be separated based on size.
Standard approaches to typing degraded DNA rely on technologies that are expensive, require instrumentation that is not widely available to the forensic community, or have greatly reduced discriminatory power. Current forensic DNA laboratory workflow is based on the separation of amplified fluorescent labeled DNA fragments by capillary electrophoresis. Substituting one set of primers for another and separating based on fragment length is both cost effective and requires little additional training of existing laboratory staff. One method of doing this is to design primers around small INDEL in the genome so primers would be designed to set just outside of the INDEL. Depending on the distribution of the insertion or deletion alleles in populations, an INDEL allele could be selected to tell an individual from another regardless of population affinity or whether an individual was from a certain ancestral population. The latter application could be valuable in cases where there are no suspects and investigators are searching for leads as to the identity of potential suspects. One objective of this project was to select two panels of INDEL markers for human identification and ancestry identification. A second objective was to design primers for the developed two panels; and the third objective was to develop multiplex assays based on the outcomes from the two aforementioned objectives. To date, the first two objectives have been completed, and the third objective will be pursued when the final project funds are released for the completion of the project as proposed. 26 figures, 13 tables, 57 references, and a listing of project publications

Date Published: July 1, 2016