Post Coital DNA Recovery

In most jurisdictions, post-coital samples are collected up to, but not after,
72 hours following rape. Today, recovery and analysis is improved through DNA technology 'identifying individuals from sperm found 7 days after coitus. The goals of this research are to answer: (1) what is the time frame for sperm recovery post coitus using Y-STR laboratory methods?, and (2) what are physiological conditions that may impact recovery of DNA in post-coital samples? The objective of this research is to provide evidence to support or limit the expansion of the 72-hour time frame for evidence collection from the vagina and cervix after a rape event in adult females. A convenience sample of 300 sexually active heterosexual female forensic RNs, >18 years of age, with normal menstrual cycles will be asked to enroll in the study over a 3 year period of time (Year 01:18-35; Year 02:36-55; Year 03:>55). Before the target coitus, the RN subject will abstain or use barrier methods 7 days prior to coitus. She will evaluate the appearance of her vulva/hymen and will answer on-line questions about her overall reproductive health and sexual activity. Before coitus, the RN will collect samples from her partner's cheek and her proximal vagina and cervix as controls. After coitus, samples will be collected on Days 3, 5, 7, 9, or 12-15 post coitus. She will abstain or use barrier methods throughout the 2-week collection period. Samples will be mailed directly to the National Center for Forensic Science DNA laboratory for indexing and Y-STR DNA analysis. Data from the analysis will be entered by the laboratory personnel using a unique identifier, exported to a raw data file, sent to and analyzed by the statistician using descriptive statistics and ANOVA. Variables identified by the expert advisory group that impact DNA recovery will be analyzed using ANOVA (e.g., date of last menstrual period, birth control method, Gravid and Para status, medications, and condom type, to name a few). This study would provide that evidence necessary for expansion (or not) of the time for SART programs nationally. ca/ncf