DYS464: A Multi-Copy Y-STR Marker
Participants: John M. Butler and Richard Schoske
Project Timeframe: July 2002 to September 2003
Purpose: The Y-chromosome short tandem repeat (Y-STR) marker DYS464 was first reported by Redd et al. Forensic Sci. Int. (2002) 130:97-111 and appears to be the most polymorphic Y-STR marker discovered to-date. A single primer pair can generate up to four distinct peaks. A careful mapping of DYS464 primers into the human genome reveals at least four copies occur over a 1.8 megabase (Mb) stretch near the DAZ region around 25 Mb on the Y-chromosome. Allele calls can be made based on peaks that are present (conservative approach) or a combination of alleles and peak height ratios (expanded typing method). However, the multitude of possible two and three peak patterns can potentially make this marker difficult to reliably type if mixtures from multiple males are involved.
Progress: Issues of peak height ratio consistency were examined in the context of different DYS464 patterns and discussed in terms of deciphering mixtures and potential degraded DNA profile patterns. We have observed 113 different DYS464 peak patterns using the conservative approach and 179 with the expanded typing method in 679 males from three U.S. populations. By comparison, in the same data set only 56 unique DYS385 types were seen. Perhaps more importantly, the addition of DYS464 results to the 9-locus minimal haplotype resulted in the ability to resolve almost all of the samples in our data set possessing the most common type that occurs in the European Y-STR Haplotype Reference Database (www.ystr.org). Several primer pairs have been developed for DYS464 and included in new multiplex assays.
Publications or Presentations Resulting From This Project:
Butler, J.M. and Schoske, R. (2005) U.S. population data for the multi-copy Y-STR locus DYS464. J. Forensic Sci. 50(4): 975-977.
Butler, J.M. and Schoske, R. (2004) Forensic value of the multi-copy Y-STR marker DYS464. Progress in Forensic Genetics 10, Elsevier Science: Amsterdam, The Netherlands, International Congress Series 1261, 278-280.
John Butler poster at International Society of Forensic Genetics - 20th International Congress ISFG (Arcachon, France), September 9-13, 2003, "Forensic Value of the Multi-Copy Y-STR Marker DYS464" [.pdf]
Redd, A.J., Agellon, A.B., Kearney, V.A., Karafet, T., de Knijff, P., Park, H., Butler, J.M., Hammer, M.F. (2002) Forensic value of fourteen novel STRs on the human Y chromosome. Forensic Sci. Int. 130: 97-111.
Last updated: 06/19/2007
Disclaimer: This project was supported by National Institute of Justice Grant Number 2003-IJ-R-029, which is an interagency agreement between NIJ and the NIST Office of Law Enforcement Standards, awarded by the National Institute of Justice, Office of Justice Programs, US Department of Justice. Points of view in this document are those of the authors and do not necessarily represent the official position or policies of the US Department of Justice. Certain commercial equipment, instruments and materials are identified in order to specify experimental procedures as completely as possible. In no case does such identification imply a recommendation or endorsement by the National Institute of Standards and Technology nor does it imply that any of the materials, instruments or equipment identified are necessarily the best available for the purpose.