Detection of prostate specific antigen and semenogelin in specimens from female rape victims

https://doi.org/10.1016/j.jflm.2017.12.017Get rights and content

Highlights

  • •

    Sperm test is confirmation of semen detection in alleged rape cases.

  • •

    Semen biomarkers are valuable indicators despite not being confirmatory tests.

  • •

    Semenogelin and PSA tests are readily available, convenient, fast and cheap to run.

  • •

    We directly compared detection rate and persistence of semen biomarkers over time.

  • •

    Semenogelin is preferable to PSA based on sensitivity, specificity and persistence.

Abstract

The presence of semen is generally accepted as evidence in sexual assault cases prosecution. Detection of sperm is confirmation of semen; however, sperm cannot always be detected. Prostate specific antigen (PSA) and semenogelin (Sg) are used as semen biomarkers. We compared the detection rate and persistence of sperm, PSA and Sg over a range of time intervals from the time of assault to specimen collection.

The results show that sperm had the longest persistence and highest detection rate. The detection rate of the Sg test was significantly better than that of the PSA test overall, whether the sperm test was negative or positive.

In conclusion, the detection of sperm should be the first test executed: if sperm is not detected, the Sg test is more suitable than the PSA test and could be used up to 72 h after assault.

Section snippets

Materials and methods

We reviewed all cases of female victims raped by men over a period of 5 years (2011–2015) then selected particular cases using six criteria: (1) women examined at Siriraj Hospital; (2) case circumstances indicating that sexual assault may have occurred (i.e. non-consensual sexual contact); (3) women having physical wounds on the body or genitalia, or substantial evidence that these women were under duress, or under the influence conscious-altering drugs (i.e alcohol, ketamine, etc.). Under Thai

Results

The sensitivity of the sperm test, Sg test and PSA test in serial dilution is shown in Table 1. PSA sensitivity was better than Sg when dilution was more than 1:200 and better than the sperm test when dilution was more than 1:1000. All had negative results in female urine, female median cubital blood, menstrual blood and male urine.

Between January 2010 and April 2015, 1764 cases of sexual assault were recorded at the Department of Forensic Medicine, Siriraj Hospital. Only 114 cases met our

Discussion

Our analysis revealed several interesting findings. First, Sg persists longer, and the Sg test has a better detection rate when compared with its PSA counterpart, except for the 24 h window when the sperm test is positive. Second, the sperm test performs better than both Sg and PSA tests, and sperm persists longer than Sg or PSA with the tests used and within the timeframes we studied.

Regarding the sensitivity of the sperm test, the Sg test and the PSA test for detection of seminal fluid in

Conclusion

This study indicates that Sg testing of forensic casework specimens is more reliable than PSA testing, based on its detection rate and persistence across almost all the time periods we investigated. In real-world cases, when considering detection rate, evidence persistence and economic viability, the sperm test should still be the first priority. If this is negative, the next most suitable test is the Sg test, rather than the PSA test, especially for specimens collected between 24 h and 72 h

Ethical approval

This study was approved by the Siriraj Institutional Review Board.

Conflict of interest

The authors have no conflicts of interest to declare.

Acknowledgments

This study was supported by a Routine to Research (R2R) grant, Faculty of Medicine Siriraj Hospital, Mahidol University, Thailand (R2R.290/15).

The authors wish to thank Mr. Suthipol Udompunthurak for statistical analysis support.

References (38)

  • V.L. Bonilha et al.

    Characterization of semenogelin proteins in the human retina

    Exp Eye Res

    (2006)
  • I. Sato et al.

    Rapid detection of semenogelin by one-step immunochromatographic assay for semen identification

    J Immunol Meth

    (2004)
  • P.J. Hooft et al.

    Bayesian evaluation of the modified zinc test and the acid phosphatase spot test for forensic semen investigation

    Am J Forensic Med Pathol

    (1997)
  • J.A. Soares-Vieira et al.

    Y-STRs in forensic medicine: DNA analysis in semen samples of azoospermic individuals

    J Forensic Sci

    (2007)
  • G.F. Sensabaugh

    Isolation and characterization of a semen-specific protein from human seminal plasma: a potential new marker for semen identification

    J Forensic Sci

    (1978)
  • J.C. Herr et al.

    Characterization of a monoclonal antibody to a conserved epitope on human seminal vesicle-specific peptides: a novel probe/marker system for semen identification

    Biol Reprod

    (1986)
  • Á. Laffan et al.

    Evaluation of semen presumptive tests for use at crime scenes

    Med Sci Law

    (2011)
  • K. Yoshida et al.

    Quantification of seminal plasma motility inhibitor/semenogelin in human seminal plasma

    J Androl

    (2003)
  • H. Lilja et al.

    The predominant protein in human seminal coagulate

    Scand J Clin Lab Invest

    (1985)

    • Cited by (0)

    View full text
    © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.