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Ultra-High Discrimination Y Chromosome Short Tandem Repeat Multiplex DNA Typing System

NCJ Number
PLoS ONE Volume: 8 Issue: 2 Dated: August 2007 Pages: 1-14
Date Published
August 2007
14 pages

This study tested 91 loci for their relative ability to increase the discrimination potential of the commonly used "core" Y-STR loci.


The result of this testing was the development of an ultra-high discrimination (UHD) multiplex DNA typing system that allows for the robust co-amplification of 14 non-core Y-STR loci. Population studies with a mixed African-American and American-Caucasian sample (n = 572) indicated that the overall discriminatory potential of the UHD multiplex was superior to all commercial kits tested. The combined use of the UHD multiplex and the Applied Biosystems' AmpFlSTR Yfiler kit resulted in 100-percent discrimination of all individuals within the sample set. These findings are relevant for sexual assault investigations in identifying a male donor DNA profile in the presence of excess quantities of female DNA. The UHD multiplex DNA typing system is particularly useful in those cases where additional discriminatory power is desired or there is a coincidental Y-STR match between potential male participants in the offense. Descriptions of methods used address the preparation of body fluid stains, DNA isolation and purification, Differential cell lysis for the recovery of sperm, DNA isolation and purification of dried blood samples, DNA quantitation, characterization of genetic markers, multiplex system development, standard PCR conditions, and PCR product detection. Also described are the multiplex system performance, mixture studies, environmentally impacted blood samples, mixed casework samples, and population studies. 5 tables, 6 figures, and 55 references

Date Published: August 1, 2007