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Search Publications by: John Butler (Fed)

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Displaying 51 - 75 of 203

Developmental Validation of the PowerPlex(R) ESI 17 Pro System

December 27, 2012
Author(s)
Carolyn R. Steffen, Margaret C. Kline, John Butler, Robert S. McLaren, Jaynish Patel, Margaret Ewing, Douglas R. Storts, Fabrice Noel, Sophie Dognaux
The SE33 locus is one of the most polymorphic markers used in human identification. However, it also possesses multiple microvariants both within the repeat and in the flanking regions. Such flanking region mutations can generate discordant allele calls

The Latest and Greatest NIST PCR-based DNA Profiling Standard: Updates and Status of Candidate Standard Reference Material (SRM) 2391c

November 1, 2011
Author(s)
Margaret C. Kline, Carolyn R. Steffen, Jamie L. Almeida, Erica L. Romsos, Michael D. Coble, John M. Butler
Standard Reference Material 2391c (SRM 2391c) PCR-based DNA Profiling Standard is the third renewal of this SRM, originally released in 1995. SRM 2391c consists of 6 candidate components labeled A through F. Components A through D are supplied as genomic

STR Sequence Analysis for Characterizing Normal, Variant, and Null Alleles

August 1, 2011
Author(s)
Margaret C. Kline, Carolyn R. Steffen, John M. Butler, Amy Decker
DNA sequence variation is known to exist in and around the repeat region of short tandem repeat (STR) loci used in human identity testing. While the vast majority of STR alleles measured in forensic DNA laboratories worldwide type as "normal" alleles

Metrology Needs and NIST Resources for the Forensic DNA Community

June 1, 2011
Author(s)
Michael D. Coble, Margaret C. Kline, John M. Butler
With the advent of Forensic DNA profiling in the mid-1980s, this technology has had a positive impact on the criminal justice system, helping to convict the guilty and exonerate the innocent. The field has evolved from focusing on multi-locus markers

Scientific Issues with Analysis of Low Amounts of DNA

September 7, 2010
Author(s)
John Butler, Becky Steffen
Faced with limited evidence that yield low amounts of DNA, forensic analysts will continually have to confront the question of how far to push DNA testing techniques. Low copy number (LCN) analysis, also known as low template DNA (LT-DNA) testing, involves

Strategies for Concordance Testing

May 1, 2010
Author(s)
Carolyn R. Steffen, David L. Duewer, Margaret C. Kline, John M. Butler
Concordance evaluations are important to conduct to determine if there are any allelic dropout or “null alleles” present in a data set. These studies are based on the fact that there are a variety of commercial short tandem repeat (STR) multiplex kits

A New 26plex Autosomal STR Assay to Aid Human Identity Testing*(dagger)

September 1, 2009
Author(s)
Carolyn R. Steffen, John M. Butler, Peter Vallone
Multiplex polymerase chain reaction (PCR) has become the standard in forensic testing. Currently there are two commercial multiplex PCR amplification kits available that simultaneously amplify 16 short tandem repeat (STR) loci that include the 13 FBI

Demonstration of Rapid Multiplex PCR Amplification Involving 16 Genetic Loci

December 1, 2008
Author(s)
Peter Vallone, Carolyn R. Steffen, John M. Butler
Current forensic DNA typing is conducted in approximately eight to ten hours with steps including DNA extraction, quantitation, polymerase chain reaction (PCR) amplification of multiple short tandem repeat (STR) loci, capillary electrophoresis separation

Addressing Y-Chromosome Short Tandem Repeat(Y-STR) Allele Nomenclature

November 25, 2008
Author(s)
John M. Butler, Margaret C. Kline, Amy E. Decker
Currently 120 different Y-chromosome short tandem repeat (Y-STR) markers are used by various genetic genealogy testing laboratories. In some cases, different laboratories may designate the same Y-STR allele with two different nomenclatures making data

An Investigation of Discrimination Capacity and the Cause of Null Alleles in Linear Array Mitostrips Using Control Region Sequence Data.

October 16, 2008
Author(s)
Michael D. Coble, Margaret C. Kline, Janette W. Redman, Amy E. Decker, Peter Vallone, John Butler
Mitochondrial DNA (mtDNA) analysis of forensic evidentiary materials such as degraded bones and shed hairs can provide the forensic scientist with some genetic information especially when highly discriminatory systems, such as nuclear STRs, completely fail