A Tool for Validating Kinship Analysis Software
This webpage was originally authored by Dr. Kristen Lewis O'Connor (NIST NRC postdoc Dec 2009- Sept 2011).
*Notice: The California Criminalistics Institute (CCI) held two 5-day courses on kinship analysis taught by Steven Myers and Brian Harmon from the California Department of Justice (August 11-15, 2014 and March 9-13, 2015). For more information, see http://oag.ca.gov/cci/description/kinship-analysis. Application forms are available at http://ag.ca.gov/cci/forms.php. A full listing of CCI courses is available at http://oag.ca.gov/cci/course-schedule.
A Need for Standard Reference Family Data
Many software tools are commercially or freely available to aid kinship analysis; however, there is no standard dataset of familial genotypes to help validate calculations made by a software program. Currently, a laboratory must generate pedigrees and genotypes for individuals with known familial relationships. These genotypes are either simulated or taken from previous casework in the laboratory. We have developed standard reference family data (SRFD) as a tool to aid laboratory validation of kinship analysis software.
The Utility of Standard Reference Family Data
We have provided an artificial four-generation pedigree based on data collected from six different Caucasian family groups analyzed with 46 autosomal STRs and 17 Y-STRs. The genotypes of the pedigree reflect observed Mendelian inheritance patterns, including mutations, rare alleles, and null alleles within real families. The pedigree structure allows for kinship testing of pairwise comparisons (parent-offspring, full siblings, half siblings, first cousins, etc.), paternity trios, and motherless paternity. Due to the size of the pedigree, more complex tests (e.g., incest) can be constructed in the future.
The SRFD can be used to verify the functionality of calculations performed within kinship analysis programs including the handling of mutations, rare alleles, and null alleles. Illustrations of how the pedigree data can be used have been demonstrated with a commercially available program and an Excel®-based freeware program (poster presented at Promega 2010 meeting).
Use the SRFD pedigree to identify the type of familial relationship to be tested and the corresponding sample numbers. For the selected samples, download the corresponding genotype data.
Autosomal STR Genotypes
SRFD genotypes for 13 STR loci (CODIS core). Download as: Text
SRFD genotypes for 15 STR loci (Identifiler). Download as: Text
SRFD genotypes for 16 STR loci (ESI 17 System). Download as: Text
SRFD genotypes for 25 STR loci (NIST 26plex). Download as: Text
SRFD genotypes for 15 STR loci (PowerPlex 16). Download as: Text
SRFD genotypes for 17 Y-STR loci (Yfiler). Download as: Text
Testing Common Paternity Index Formulas
The STR genotypes of the SRFD pedigree can be used to challenge the 20 common paternity index formulas for paternity trios (alleged father, mother, child) and motherless paternity cases (alleged father, child). These formulas can be found in Appendix 8 of the AABB Guidance for Standards for Relationship Testing Laboratories, 9th ed. (2009).
For each paternity trio or motherless paternity comparison in the SRFD pedigree, there is an AABB paternity index formula associated with each locus that can be tested or validated.
13 STR loci (CODIS core). Download as: Excel
Notations of Mutations, Rare Alleles, and Null Alleles in the Pedigree
List of mutations in the SRFD Download as: Text
List of rare alleles in the SRFD Download as: Text
List of null alleles in the SRFD Download as: Text
Identifiler (Applied Biosystems)
ESI 17 System (Promega)
NIST 26plex (in-house assay)
Y-filer (Applied Biosystems)
Allele Frequency Data
Butler, J.M., Schoske, R., Vallone, P.M., Redman, J.W., Kline, M.C. (2003) Allele frequencies for 15 autosomal STR loci on U.S. Caucasian, African American, and Hispanic populations. J. Forensic Sci. 48(4):908-911.
Butler, J.M., Decker, A.E., Vallone, P.M., Kline, M.C. (2006) Allele frequencies for 27 Y-STR loci with U.S. Caucasian, African American, and Hispanic samples. Forensic Sci. Int. 156:250-260.
Hill, C.R., Kline, M.C., Coble, M.D., Butler, J.M. (2008) Characterization of 26 miniSTR loci for improved analysis of degraded DNA samples. J. Forensic Sci. 53(1):73-80.
Hill, C.R., Duewer, D.L., Kline, M.C., Sprecher, C.J., McLaren, R.S., Rabbach, D.R., Krenke, B.E., Ensenberger, M.G., Fulmer, P.M., Stort, D.R., Butler, J.M. (2011) Concordance and population studies along with stutter and peak height ratio analysis for the PowerPlex® ESX 17 and ESI 17 Systems. Forensic Sci. Int. Genet. 5(4): 269-275.
O’Connor, K.L., Hill, C.R., Vallone, P.M., Butler, J.M. (2011) Linkage disequilibrium analysis of D12S391 and vWA in U.S. population and paternity samples. Forensic Sci. Int. Genet. 5(5): 538-540. [see also O’Connor, K.L., Hill, C.R., Vallone, P.M., Butler, J.M. (2011) Corrigendum to "Linkage disequilibrium analysis of D12S391 and vWA in U.S. population and paternity samples" Forensic Sci. Int. Genet. 5(5): 541-542.]
Algorithms for Kinship Statistics
AABB. (2009) Guidance for Standards for Relationship Testing Laboratories, 9th ed. AABB, Bethesda, Maryland, 165 pp.
Buckleton J., Triggs C., Walsh S. (2005) Forensic DNA Evidence Interpretation, CRC Press, Boca Raton, Florida, 534 pp.
Evett I., Weir B. (1998) Interpreting DNA Evidence. Statistical Genetics for Forensic Scientists, Sinauer Associates, Sunderland, Massachusetts, 278 pp.
Gjertson D.W., et al. (2007) ISFG: Recommendations on biostatistics in paternity testing. Forensic Sci. Int. Genet. 1(3-4): 223-231.
Slooten, K. (2011) Validation of DNA-based identification software by computation of pedigree likelihood ratios. Forensic Sci. Int. Genet. 5(4): 308-315.
Last Updated: 05/15/2015