How can you minimize DNA contamination during evidence collection at a scene?

How can you minimize DNA contamination during evidence collection at a scene?

• A. Use new gloves for each item, change gloves between items, sterile tools, avoid touching DNA-rich areas, and segregate evidence.
• B. Use the same gloves for all items to save time.
• C. Handle DNA-rich areas with gloves off
• D. Allow evidence to touch any surface before packaging

Answer: (B)

Minimizing DNA contamination at a scene relies on strict control of who and what touches each item. The best approach is to use fresh gloves for every item, change gloves between items, employ sterile tools, avoid touching DNA-rich areas, and keep evidence separated to prevent cross-transfer. This disciplined handling keeps DNA from one item from being carried to another, preserves the integrity of each piece of evidence, and reduces the chance of introducing extraneous DNA from the scene or the handler. Using the same gloves for all items would enable DNA to transfer between items, increasing cross-contamination. Handling with gloves off exposes DNA to the environment and to other surfaces, and letting evidence touch surfaces before packaging creates more opportunities for foreign DNA to be deposited.

Minimizing DNA contamination at a scene relies on strict control of who and what touches each item. The best approach is to use fresh gloves for every item, change gloves between items, employ sterile tools, avoid touching DNA-rich areas, and keep evidence separated to prevent cross-transfer. This disciplined handling keeps DNA from one item from being carried to another, preserves the integrity of each piece of evidence, and reduces the chance of introducing extraneous DNA from the scene or the handler.

Using the same gloves for all items would enable DNA to transfer between items, increasing cross-contamination. Handling with gloves off exposes DNA to the environment and to other surfaces, and letting evidence touch surfaces before packaging creates more opportunities for foreign DNA to be deposited.