Semen is crucial evidence for some sex crimes, with its sole confirmation being sperm detection. The success of sperm detection is dependent on all levels of preanalytic and analytic procedures. Specimen collection must be performed by well-trained and competent forensic physicians as well as forensic nurses, with preservation done properly before laboratory transfer. Laboratory procedures should consider archival sperm identification, by visualization, with adequate amounts separated from other cells to obtain male DNA profiles. Differential extraction is robust and accepted as the forensic standard but is time consuming and may result in male DNA loss. Thus, alternative methods and microdevices have been developed. Challenges in sperm isolation from vaginal or buccal epithelium mixes and discrimination in multiperpetrator cases have been overcome by single-cell profiling; however, problems inherent in identical twin discrimination and azoospermia have yet to be solved. Epigenetics and future molecular biomarkers may hold the key; therefore, all laboratory processes must consider DNA and RNA protection. Long-term specimen preservation should be done when possible in light of future confirmatory tests.
From the Department of Forensic Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Manuscript received May 5, 2019; accepted September 4, 2019.
This article does not contain any studies with (living) human participants or animals performed by the author.
This review was supported by a Chalermphrakiat Grant grant of from Siriraj Hospital, Faculty of Medicine, Mahidol University, Thailand.
The author has no conflicts of interest to declare.
Reprints: Papanu Suttipasit, MD, Department of Forensic Medicine, Siriraj Hospital, Mahidol University, 2 Wonglang Rd, Bangkoknoi District, Bangkok 10700, Thailand. E-mail: firstname.lastname@example.org; email@example.com.
Online date: November 4, 2019