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Making Your Own DNA Kit

DNA evidence, when properly preserved, can assist law enforcement a great deal.

Please use the following easy steps to preserve the DNA of your family member properly.

  1. Dental impression:  Using a Styrofoam cup, have your child bite down on the cup hard enough to see the upper and lower imprints. Label the cup with your child's name and note which is "upper" and "lower."
  2. Hair strands:  Pull 4-5 strands of hair out of your child's head at the root and place in an envelope. Label the envelope with your child's name and date of collection. You can also save fingernail and toenail clippings in the same envelope.
  3. Blood sample:  Air dry a freshly blood-stained Band-Aid overnight and seal it in a small envelope. Then place the envelope in a non-plastic container.  Label it with your child's name and date of collection and place it in the freezer.
  4. Cheek swab:  Take a clean/sterile cotton swab and rub it inside your child's cheek, dampening it with saliva.  Air-dry overnight and seal it in a small envelope.  Then place in a separately labeled non-plastic container and preserve in the freezer.


Preserving DNA Samples

A recent Task Force Report and Update issued by the State of California Department of Justice provided these sample preservation tips :

  • Store samples in a dried condition, frozen storage, or in a controlled room temperature environment with little fluctuation in temperature or humidity.
  • Plastic is not recommended for storage of biological evidence.
  • If samples are stored in the family freezer, it is critical that samples are not thawed and not contaminated by other items in the freezer.
  • Do not allow frozen DNA samples to thaw as evidence will be destroyed.



External Links

Amber Center for Missing & Exploited Children: 1-800-541-0777


This City of Stockton web page last reviewed on --- 5/21/2015