DNA can be spread through various means involving the transfer of bodily fluids or through direct contact. Here's a breakdown:
DNA is spread primarily through the transfer of biological material containing cells with DNA. This material includes:
- Bodily Fluids: Blood, saliva, and semen are common vehicles for DNA transfer. For example, if a person drops their blood after sustaining an injury, spits saliva, or ejaculates semen onto a surface or another person, their DNA is transferred.
- Direct Contact: DNA can be transferred through touching objects or surfaces with bare hands. This occurs because skin cells containing DNA are left behind. Likewise, touching another person's bare hand with your bare hand can also transfer DNA. This is also referred to as touch DNA.
In summary, DNA is spread through activities that cause transfer of cells containing it, such as physical contact or the shedding of bodily fluids.
