In evidence collection, which method is considered the preferred approach for DNA sampling when suspect information is not available?

• A. Ink Stamping
• B. Tape Lift
• C. Print
• D. Swab

Answer: (D)

When you’re collecting DNA evidence without any suspect information, the goal is to retrieve cellular material directly from biological sources in a way that preserves the DNA for lab analysis. A sterile swab is the best tool for this because it can be used on a wide range of surfaces and materials, easily collecting epithelial cells or trace material without causing damage to the evidence. Using a moistened swab helps lift cells from dry surfaces, increasing the amount of DNA recovered while keeping the sample relatively uncontaminated and easy to store with proper chain-of-custody.

Tape lifts can grab material, but the adhesive and the method can complicate extraction or leave residues that interfere with analysis, making swabs the more reliable choice in most cases. Ink stamping and fingerprint prints aren’t designed to collect or preserve genetic material, so they’re not used for DNA analysis. Swabbing stays the most versatile and efficient approach when there’s no information about a suspect.