Separate analysis of DYS385a and b versus conventional DYS385 typing: is there forensic relevance?
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In order to determine to what extent the separate analysis of both copies of DYS385 improves Y-chromosomal short tandem repeat (Y-STR) haplotyping, we followed a recently published protocol for the separate amplification of DYS385a and DYS385b with modifications and compared the results with those obtained by conventional analysis in a population sample comprising 133 unrelated Caucasian males from Austria. Additionally, we typed all markers of the minimal haplotype (minHT) and a set of Y-chromosomal single nucleotide polymorphisms (Y-SNPs) in order to interpret the STR data depending on the Y-SNP haplogroup structure. The separate amplification of DYS385a and b improved the power of discrimination of this marker when compared to the results obtained with the conventional non-locus-discriminating amplification strategy. However, the degree of this improvement varied greatly between different haplogroups and was found to be highest in clade K. In the forensically relevant context of the minHT, the separate analysis of the DYS385 alleles had no effect on the differentiation of paternal lineages in our study. Furthermore, the amplicon lengths of 700–780 base pairs obtained in the course of the locus-discriminating approach restrict the applicability of this amplification strategy to high quality DNA samples.
KeywordsY chromosome DYS385 Y-STR Y-SNP haplogroups Population study
We thank Alexandra Lindinger for excellent technical assistance and two anonymous reviewers for valuable comments and suggestions regarding the designation of DYS385 phenotypes.
- Berger B, Hölzl G, Oberacher H, Niederstätter H, Huber CG, Parson W (2002) Single nucleotide polymorphism genotyping by on-line liquid chromatography-mass spectrometry in forensic science of the Y-chromosomal locus M9. J Chromatogr B 782:89–97Google Scholar
- Gill P, Brenner C, Brinkmann B et al. (2001) DNA Commission of the International Society of Forensic Genetics: recommendations on forensic analysis using Y-chromosome STRs. Int J Legal Med 114:305–309, Forensic Sci Int 124:5–10Google Scholar
- Parson W, Niederstätter H, Köchl S, Steinlechner M, Berger B (2001) When autosomal short tandem repeats fail: optimized primer and reaction design for Y-chromosome short tandem repeat analysis in forensic casework. Croat Med J 42:285–287Google Scholar
- Santos FR, Carvalho-Silva DR, Pena SDJ (1999) PCR-based DNA profiling of human Y chromosomes. In: Epplen JT, Lubjuhn T (eds) Methods and tools in biosciences and medicine. Birkhäuser, Basel, pp 133–152Google Scholar
- Schneider S, Roessli D, Excoffier L (2000) Arlequin ver. 2.000: a software for population genetics data analysis. Genetics and Biometry Laboratory, University of Geneva, SwitzerlandGoogle Scholar
- Y Chromosome Consortium (2003) A nomenclature system for the tree of human Y-chromosomal binary haplogroups. Genome Res 12:339–348Google Scholar