Blood samples come in a variety of forms including fresh (whole) blood, blood stains on tissue or other absorbent materials and dried blood stains. A fresh blood sample is as effective as a buccal swab for providing DNA. The probability of success of DNA extraction from blood stains or dried blood will depend on the level of decomposition of the blood and whether any contaminating substances are present that can interfere with DNA extraction (this can be due to contamination from chemicals, human sources or from being exposed to the elements). Whole blood should be taken at the hospital in an EDTA vacutainer and may be stored for 24 hours at 4 °C before submitting for DNA testing. When submitting blood stains or dried blood for DNA testing please ensure the following
Wear gloves when handling the sample to avoid contamination
Using gloves, place the sample in a plastic bag and send to DTL for testing
Finally, place the plastic bag into the DTL self-addressed envelope with your submission form and send back to DTL for processing.
