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I was reading this article : Perspiration
The first question which came to my mind after reading the composition of sweat was whether it contains any information about the DNA or not?

I haven't had much interaction with biology since 12th grade (2010), so kindly answer in layman's terms and detail as well.

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    $\begingroup$ The consensus of the answers as of March, 2023 seems to be that human sweat does not contain enough human DNA to identify the person producing that sweat. This contradicts fictional court testimony in s1 e1 of "All Rise", a crime drama on Hulu subscription video. DNA identification of human fluids apparently requires them to contain human cells. $\endgroup$ Commented Mar 14, 2023 at 19:52

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The Wikipedia page you linked says that sweat is composed of a liquid similar to blood plasma. As all DNA in humans is stored in the nucleus of a cell, it seems unlikely that the sweat itself would contain any DNA.

However, when someone sweats significantly, I can't imagine that no skin cells end up in the sweat. In any case in which this occurs, then the DNA in the cell is in the sweat. Additionally, with small amounts of sweat, I can't imagine how it would be collected without getting any skin cells in it.

This source confirms that sweat contains DNA in some form. Additionally, I think the following quote from here shows that it is stored in cells:

In every case, what is being tested is the DNA contained in cells of human tissue

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  • $\begingroup$ Yes exactly. it was due to a heated discussion with a friend. We were discussing about DNA, I was sayin about how bodily fluids like blood, semen, etc contain genetic information. She said that sweat doesn't and I couldn't find enough evidence to prove otherwise. $\endgroup$
    – ABcDexter
    Commented Apr 19, 2016 at 8:20
  • $\begingroup$ @ABcDexter AFAIK, those fluids only contain DNA because they contain cells. I'm not an expert, by any means, though. $\endgroup$
    – john01dav
    Commented Apr 19, 2016 at 8:21
  • $\begingroup$ @Christiaan I've found and added some sources that seem reliable. $\endgroup$
    – john01dav
    Commented Apr 19, 2016 at 8:43
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    $\begingroup$ @john01dav - great +1 $\endgroup$
    – AliceD
    Commented Apr 19, 2016 at 8:47
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    $\begingroup$ So sweat does contain DNA and the genetic information ;) $\endgroup$
    – ABcDexter
    Commented Apr 19, 2016 at 8:50
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I believe the answer is no.

Sweat is the liquid secretion of body cells, not including the cells themselves. If the cells are secreted when sweating, then you may find some DNA in your sweat. You are right on that. Serum contains many different types of lymphocytes, the majority of them--mature red blood cells, don't have nucleus. So they don't contain DNA. And, live skin cells cannot be sweated. Dead skin cells are easily found on the mucosal tissues of your body, however mucosal tissues cannot sweat! In a word, it's basically impossible to see DNA in sweat.

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    $\begingroup$ @ABcDexter In respect to your comments, semen is for sure to contain genetic information because of the presence of germ cells(sperms) in it. However, it's not the same way of how you sweat. Semen is from sex organs only while you can't say sweat is from a specific organ. $\endgroup$
    – Young
    Commented Apr 19, 2016 at 20:12
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Yes but not humans DNA

Sweat does not normally contain human DNA, it does not pick up many skin cells under normal conditions, excessive sweat can pick up some however. However sweat is colonized by bacteria fairly quickly once it reaches the surface of the skin so unless you are extracting it directly from the gland it will contain bacteria with their own DNA.

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