Forensic Science International: Genetics Supplement Series
Volume 1, Issue 1 , Pages 4-6, August 2008

Locked nucleic acids: Increased trace DNA amplification success with improved primers

  • K.N. Ballantyne

      Affiliations

    • Victoria Police Forensic Services Department, Macleod 3085, Victoria, Australia
    • Genetics Department, La Trobe University, Melbourne 3086, Victoria, Australia
    • Corresponding Author InformationCorresponding author at: 31 Forensic Drive, Macleod 3085, Victoria, Australia. Tel.: +61 3 9450 3519; fax: +61 3 9450 3601.
    • ,
  • R.A.H. van Oorschot

      Affiliations

    • Victoria Police Forensic Services Department, Macleod 3085, Victoria, Australia
    • ,
  • R.J. Mitchell

      Affiliations

    • Genetics Department, La Trobe University, Melbourne 3086, Victoria, Australia

Received 14 August 2007; accepted 7 October 2007.

Abstract 

Locked nucleic acids (LNAs) are a conformationally restricted DNA analog, which can be incorporated into oligonucleotides to increase binding strength. To investigate if LNAs increase amplification success for trace DNA samples in a forensic context, primer sequences for four routinely used STR loci (FGA, D7S820, D13S317 and D18S51) have been altered to include LNA bases. The LNA modified primers display a broader tolerance to a range of reaction conditions compared to unmodified DNA primers, with higher Tms giving increased specificity. Increased peak heights, improved peak height ratios and decreased template requirements were seen with LNA primers. The increased amplification success of LNA primers, and broader range of optimal reaction conditions, suggest that using LNA primers for multiplex STR genotyping assays could be highly beneficial for trace DNA genotyping.

Keywords: Locked nucleic acids, Low-copy number, Multiplexing, Amplification

 

PII: S1875-1768(08)00083-8

doi:10.1016/j.fsigss.2007.10.052

Forensic Science International: Genetics Supplement Series
Volume 1, Issue 1 , Pages 4-6, August 2008

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