TY - JOUR
T1 - The effect of wild card designations and rare alleles in forensic DNA database searches
AU - Tvedebrink, Torben
AU - Bright, Jo-Anne
AU - Buckleton, John S
AU - Curran, James M
AU - Morling, Niels
N1 - Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
PY - 2015/5/1
Y1 - 2015/5/1
N2 - Forensic DNA databases are powerful tools used for the identification of persons of interest in criminal investigations. Typically, they consist of two parts: (1) a database containing DNA profiles of known individuals and (2) a database of DNA profiles associated with crime scenes. The risk of adventitious or chance matches between crimes and innocent people increases as the number of profiles within a database grows and more data is shared between various forensic DNA databases, e.g. from different jurisdictions. The DNA profiles obtained from crime scenes are often partial because crime samples may be compromised in quantity or quality. When an individual's profile cannot be resolved from a DNA mixture, ambiguity is introduced. A wild card, F, may be used in place of an allele that has dropped out or when an ambiguous profile is resolved from a DNA mixture. Variant alleles that do not correspond to any marker in the allelic ladder or appear above or below the extent of the allelic ladder range are assigned the allele designation R for rare allele. R alleles are position specific with respect to the observed/unambiguous allele. The F and R designations are made when the exact genotype has not been determined. The F and R designation are treated as wild cards for searching, which results in increased chance of adventitious matches. We investigated the probability of adventitious matches given these two types of wild cards.
AB - Forensic DNA databases are powerful tools used for the identification of persons of interest in criminal investigations. Typically, they consist of two parts: (1) a database containing DNA profiles of known individuals and (2) a database of DNA profiles associated with crime scenes. The risk of adventitious or chance matches between crimes and innocent people increases as the number of profiles within a database grows and more data is shared between various forensic DNA databases, e.g. from different jurisdictions. The DNA profiles obtained from crime scenes are often partial because crime samples may be compromised in quantity or quality. When an individual's profile cannot be resolved from a DNA mixture, ambiguity is introduced. A wild card, F, may be used in place of an allele that has dropped out or when an ambiguous profile is resolved from a DNA mixture. Variant alleles that do not correspond to any marker in the allelic ladder or appear above or below the extent of the allelic ladder range are assigned the allele designation R for rare allele. R alleles are position specific with respect to the observed/unambiguous allele. The F and R designations are made when the exact genotype has not been determined. The F and R designation are treated as wild cards for searching, which results in increased chance of adventitious matches. We investigated the probability of adventitious matches given these two types of wild cards.
U2 - 10.1016/j.fsigen.2014.12.003
DO - 10.1016/j.fsigen.2014.12.003
M3 - Journal article
C2 - 25576850
SN - 1872-4973
VL - 16
SP - 98
EP - 104
JO - Forensic Science International: Genetics
JF - Forensic Science International: Genetics
ER -
