Sexing of forensic samples using PCR

Area of Science:

• Forensic Science
• Molecular Biology
• Genetics

Background:

• Accurate sex determination is crucial in forensic investigations.
• Traditional methods can be time-consuming or require specific sample types.
• Polymerase Chain Reaction (PCR) offers a sensitive molecular approach.

Purpose of the Study:

• To develop and validate a rapid PCR-based protocol for sex determination of forensic samples.
• To assess the applicability of the protocol to various biological evidence, including bloodstains and vaginal swabs.
• To evaluate the sensitivity and potential challenges, such as contamination, of the developed method.

Main Methods:

• Utilized three sets of primers: two specific for Y chromosome repetitive sequences and one for X chromosome repetitive sequences.
• Developed a rapid Polymerase Chain Reaction (PCR) protocol for simultaneous amplification of target sequences.
• Applied the protocol to casework samples, including dried bloodstains and a vaginal swab, with appropriate controls.

Main Results:

• The established PCR protocol successfully differentiated between male and female DNA in forensic samples.
• The method demonstrated high sensitivity, capable of sexing degraded or limited biological evidence.
• Experimental procedures, controls, and potential contamination issues were detailed and discussed.

Conclusions:

• A rapid and reliable PCR method for forensic sample sexing has been established.
• This protocol is suitable for routine application in forensic laboratories for sex determination.
• The study highlights the importance of stringent controls to mitigate contamination risks in molecular forensic analysis.