Timing Window
Definition
The period after an assault during which a specific locus is likely to yield viable foreign DNA. Windows vary substantially by locus: shorter for oral and external skin, longer for cervical and anal samples.
- Definition
- Period after assault when a locus likely yields foreign DNA
- Shorter windows
- Oral and external skin swabs
- Longer windows
- Cervical and anal swabs
- Domain
- Sexual assault forensic examination
Common questions
Why does the timing window vary so much between sample sites?+
Sites differ in how quickly saliva or semen is washed away or degraded, oral and exposed skin surfaces clear foreign material fastest through washing, eating and normal activity, while internal sites like the cervix retain material longer due to reduced exposure and slower clearance.
Does swabbing after the timing window has passed mean the exam should be skipped?+
No. Examiners still swab beyond the typical window because individual variation, the specific act involved, and other trace evidence such as injury documentation remain valuable even where DNA recovery odds have dropped.
Related terms
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- Double-Swab Technique
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- Epithelial Cell Fraction
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- Y-STR Analysis
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