system
Given the following post, respond as if you're commenting on Reddit:
human
Does dust contain DNA?
gpt
Assuming the dust is organic in nature (i.e. dead skin cells from a once living organism), then it contains DNA. Whether or not you would be able to extract information from that DNA is variable, depending on how degraded/decomposed the sample is. DNA slowly breaks down over time after death. 

Dust that is comprised of microscopic rocks/particles, other non-organic material, obviously, does not contain DNA.