NCJ Number
211287
Journal
Journal of Forensic Sciences Volume: 50 Issue: 5 Dated: September 2005 Pages: 1128-1133
Date Published
September 2005
Length
6 pages
Annotation
This study screened short tandem repeat (STR) profiles from over 32,000 individuals generated by the ABI Profiler Plus and Cofiler systems for variant alleles not represented within manufacturer-provided allelic ladders.
Abstract
For most forensic and parentage testing applications, amplified short tandem repeat (STR) alleles of tested individuals are compared to alleles comprising commercially-produced allelic ladders in order to accurately assign allele designations. Most DNA profiles are comprised of STR alleles represented within allelic ladders, however a small number of individuals harbor poorly characterized “variant” alleles absent from allelic ladders. Without confirmation of such variants, the loci involved are typically omitted from genetic analysis. In this study, STR profiles from 32,671 individuals comprised of Combined DNA Index System (CODIS) loci were generated with either both the Applied Biosystems (ABI) AmpFISTR Profiler Plus and Cofiler multiplex systems or with the Profiler Plus system only and screened for variant alleles not represented within manufacturer-provided allelic ladders. Eighty-five distinct variant alleles were identified in 757 of the more than 32,000 individuals examined. However, 242 of the 757 individuals expressing variants were children submitting for parentage testing with 1 or both parents and were therefore discarded from the analysis. In conclusion, population genetic data were identified and generated for 85 distinct variant alleles at 12 of the 13 CODIS STR loci that were not represented in commercially available allelic ladders. The variant alleles described comprise valuable tools for forensic and other human identification laboratories that use CODIS STRs. Tables and references