A proof of principal study on the use of direct PCR of semen and spermatozoa and development of a differential isolation protocol for use in cases of alleged sexual assault.
Sexual assault samples are some of the most common samples encountered in forensic analysis. These samples can require a significant time investment due to differential extraction processes. We report on the first record of successful direct amplification of semen for STR analysis. Neat seminal fluid, dilutions ranging from 1:5 to 1:160 and GEDNAP samples were successfully amplified using a direct method. A mild differential isolation technique to enrich spermatozoa was developed and successfully implemented to separate and directly amplify a mixture of semen and female epithelial cells. Aliquots of samples subjected to the differential isolation protocol were stained with Haemotoxylin and Eosin for sperm scoring. Samples stained after PCR showed a complete lack of intact spermatozoa demonstrating that the cells are lysed during the PCR process. This paper demonstrates the potential to incorporate direct PCR in cases of sexual assault to more rapidly obtain results and achieve a higher sensitivity.
Department of Chemistry and Physics, Arcadia University, 450 S. Easton Rd., Glenside, PA, 19038, USA. tobes@arcadia.edu.|School of Biological Sciences, Flinders University, Adelaide, Australia. tobes@arcadia.edu.
Shanan S
SS
Tobe
Centre for Forensic Science, WestCHEM, Technology and Innovation Centre, University of Strathclyde, Glasgow, UK.|Forensic Division, Department of Chemistry Malaysia, Jalan Sultan, Malaysia.
Yuvaneswari C
YC
Swaran
Centre for Forensic Science, WestCHEM, Technology and Innovation Centre, University of Strathclyde, Glasgow, UK.
Lynn
L
Dennany
Institute of Legal Medicine, University of Münster, Münster, Germany.
Ursula
U
Sibbing
Institute of Legal Medicine, University of Münster, Münster, Germany.
Kristina
K
Schulze Johann
Centre for Forensic Science, WestCHEM, Technology and Innovation Centre, University of Strathclyde, Glasgow, UK.
Lindsey
L
Welch
Institute of Legal Medicine, University of Münster, Münster, Germany.
Marielle
M
Vennemann
D004847:Epithelial Cells / Q000166:cytology; D005260:Female; D053803:Forensic Genetics / Q000379:methods; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction / Q000379:methods*; D012661:Semen / Q000737:chemistry*; D012742:Sex Offenses; D013094:Spermatozoa / Q000166:cytology*; D013194:Staining and Labeling
Differential isolation; Direct PCR; Semen; Seminal fluid; Sexual assault; Spermatozoa