Epithelial Cell Fraction
Definition
The non-sperm cellular material in a sexual assault sample. Contains skin and mucosal cells from both victim and any perpetrator who made contact. The target for profiling when spermatozoa are absent.
Related terms
- Azoospermia
- The absence of spermatozoa from ejaculated semen, resulting from obstructive causes (vasectomy, ductal blockage) or non-obstructive causes (testicular failure). Azoospermic semen contains...
- Differential Extraction
- A two-step DNA extraction procedure used when a stain contains both sperm cells and non-sperm epithelial cells. The first step lyses epithelial...
- Double-Swab Technique
- A collection method for dried biological stains in which a moistened swab rehydrates and lifts the stain from the surface, followed immediately...
- Timing Window
- The period after an assault during which a specific locus is likely to yield viable foreign DNA. Windows vary substantially by locus:...
- Y-STR Analysis
- Short tandem repeat profiling targeting the male-specific Y chromosome. Used when female victim DNA overwhelms the autosomal profile in a mixture, allowing...
Explained in
- Swabbing Technique and DNA YieldThe non-sperm cellular material in a sexual assault sample. Contains skin and mucosal cells from both victim and any perpetrator who made contact. The target f...