Saliva is not considered touch DNA. While saliva contains DNA, it's generally considered a biological fluid rather than the trace amounts of DNA left behind through touch.
Touch DNA refers to the microscopic amounts of skin cells transferred onto objects through contact. These cells contain DNA and can be collected for forensic analysis.
However, saliva is often collected directly from sources like cigarette butts, toothpicks, or even the mouth area of beverage containers. These items are not considered touch DNA but rather biological samples containing a higher concentration of DNA.
Here's a breakdown:
- Touch DNA: Tiny skin cells left behind on objects through contact.
- Saliva: Biological fluid containing a higher concentration of DNA.
Examples of Touch DNA:
- Skin cells left on a door handle
- Fingerprints on a glass
- Hair follicles found on a clothing item
Examples of Samples Containing Saliva (not considered touch DNA):
- Cigarette butts
- Toothpicks
- Mouth area of beverage containers (bottle/cup)
- Chewing gum
While saliva is not touch DNA, it is an important source of DNA in forensic investigations.
