title: Genetic mapping of 15 human X chromosomal forensic short tandem repeat (STR) loci by means of multi-core parallelization.
abstract: Typing of X chromosomal short tandem repeat (X STR) markers has become a standard element of human forensic genetic analysis. Joint consideration of many X STR markers at a time increases their discriminatory power but, owing to physical linkage, requires inter-marker recombination rates to be accurately known. We estimated the recombination rates between 15 well established X STR markers using genotype data from 158 families (1041 individuals) and following a previously proposed likelihood-based approach that allows for single-step mutations. To meet the computational requirements of this family-based type of analysis, we modified a previous implementation so as to allow multi-core parallelization on a high-performance computing system. While we obtained recombination rate estimates larger than zero for all but one pair of adjacent markers within the four previously proposed linkage groups, none of the three X STR pairs defining the junctions of these groups yielded a recombination rate estimate of 0.50. Corroborating previous studies, our results therefore argue against a simple model of independent X chromosomal linkage groups. Moreover, the refined recombination fraction estimates obtained in our study will facilitate the appropriate joint consideration of all 15 investigated markers in forensic analysis.
authors: Office of the Chief Scientist, Defense Forensic Science Center, Ft. Gillem, GA, USA; Analytical Services, Inc., Arlington, VA, USA.
authors: Toni Marie
authors: TM
authors: Diegoli
authors: Cologne Center for Genomics, University of Cologne, Cologne, Germany.
authors: Heinrich
authors: H
authors: Rohde
authors: Regional Computing Centre, University of Cologne, Cologne, Germany.
authors: Stefan
authors: S
authors: Borowski
authors: Institute of Medical Informatics and Statistics, Christian-Albrechts University, Kiel, Germany.
authors: Michael
authors: M
authors: Krawczak
authors: Applied Genetics Group, National Institute of Standards and Technology, Gaithersburg, MD, USA.
authors: Michael D
authors: MD
authors: Coble
authors: Cologne Center for Genomics, University of Cologne, Cologne, Germany. Electronic address: michael.nothnagel@uni-koeln.de.
authors: Michael
authors: M
authors: Nothnagel
mesh_terms: D002874:Chromosome Mapping; D041321:Chromosomes, Human, X; D003205:Computing Methodologies; D016172:DNA Fingerprinting; D005260:Female; D008040:Genetic Linkage; D005838:Genotype; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D056186:Metagenomics / Q000379:methods*; D018895:Microsatellite Repeats
keywords: Forensic analysis; Genetic linkage; Genetic mapping; High performance computing; Short tandem repeat; X chromosome