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I am writing a fictional novel about an extensively genetically engineered man, unbeknownst to him, who gets into trouble on a regular basis. The man is physically large and strong, very fast (tiger-like hand speed), and he has exceptional sensibilities such as night vision, hearing and smell. The FBI gets some of his saliva from a crime scene and creates a DNA fingerprint from it.

My question/s is: could the technicians/scientists who perform the DNA fingerprinting procedure for the FBI be able to tell that this man is different from other humans? Would it be possible for someone to be human and have a different number of chromosomes? Does all DNA fingerprinting appear as bar codes and mean nothing until compared to a sample?

Please forgive my ignorance on the subject. Thank you for any input.

Chris

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    $\begingroup$ Can you clarify what you mean by "different from other humans"? I assume you mean could they tell he was super human, not just tell him apart from other people? If it's the latter then yes, since that's basically the point of fingerprinting. $\endgroup$ – Joe Healey Jun 29 '17 at 20:03
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    $\begingroup$ You could try your question on WorldBuilding.SE, too. I'd expect there are some people there with a background in biology, at least enough to know some of these forensic techniques that are often of interest to the general public. There it would also be on-topic to ask in the style of "I want this to happen in my story, is this feasible?" for example, if you wanted a feasible way for your FBI to start to reveal the nature of this individual. @canadianer's example is about as far as we can go here without straying off topic. $\endgroup$ – Bryan Krause Jun 29 '17 at 20:25
  • $\begingroup$ Based on the answers below you could decide to have one or two modifications that showed up as odd in the fingerprinting which leads to a whole genome sequence being determined. Especially if the story is set in the near future. $\endgroup$ – Alan Boyd Jun 30 '17 at 6:07
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Could the technicians/scientists who perform the DNA fingerprinting procedure for the FBI be able to tell that this man is different from other humans?

If by different you mean genetically engineered, it depends on whether the loci tested have been engineered to such an extent that they are substantially different from other humans in order to arouse some kind of suspicion. There are other tests could be done that would show, at the least, that this individual's genome is abnormal.

Would it be possible for someone to be human and have a different number of chromosomes?

Yes, this is called aneuploidy and is the cause of many genetic disorders. Fingerprinting would not detect this.

Does all DNA fingerprinting appear as bar codes and mean nothing until compared to a sample?

DNA fingerprinting looks at sequence length polymorphisms and essentially tells you the length of certain regions of DNA in an individual. In fingerprinting, samples are compared to see whether DNA from two samples come from the same individual. A single sample obviously wouldn't work for this, but that doesn't mean it would tell you nothing.

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    $\begingroup$ Just to add, modern "fingerprinting" uses short tandem repeats that are (mostly) free of biological activity, so it seems unlikely that some engineered human would differ from his parents any more than their unmodified children would. And if there are new genes added on a new chromosome, well, those would be completely invisible to the technique unless it contained sufficient sequence similarity with one of the targeted STRs. $\endgroup$ – Bryan Krause Jun 29 '17 at 20:20
  • $\begingroup$ I find it bizarre that a comment starting with "just to add" has more up-votes than the actual answers... $\endgroup$ – canadianer Jun 29 '17 at 23:54
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To answer the questions separately:

1 - "Could the scientists tell that this man is different from other humans?"

The functional basis of DNA fingerprinting, is to use regions of DNA that are known to be highly variable between individuals, such as micro- and minisatellites (short, highly repetitive stretches of DNA).

This is explained in fairly basic terminology on the wikipedia page for the topic.

As such, if your question means "can this be used to distinguish him from other people", then the answer is yes, absolutely. That's exactly why DNA fingerprinting is used in criminal trials etc.

If the question is "could the stretches of DNA used in the fingerprinting procedure show if someone is 'super-human'" then there are 2 issues I can think of:

The first is up to you: You have the creative freedom to decide where in his DNA these alterations have been made. If the modifications are not in the areas that DNA fingerprinting would test, then no.

Since the modifications that would give marked phenotypic changes such as sight improvement etc. are likely to need be in coding DNA sequences (the ones that typically give rise to proteins, though this is an exceedingly loose definition), it's probably pretty implausible you'd be changing regions DNA fingerprinting examines. Tandem repeats dont generally have well known or defined biological roles. They're often referred to as 'junk DNA'. Though this term is falling out of favour as we're beginning to realise there are more subtleties to genome architecture.

Secondly, if we assume you do elect to modify some satellite sites, it would be extremely unlikely that this could ever be linked to 'super human' phenotypes. Determining whether or not a mutation, even in a coding sequence, where you can examine the protein product and the organism experimentally, has any biological effect, is still extremely hard to do. Not to mention, a vanishingly small number of spontaneous mutations in a sequence ever give rise to an 'improved' sequence.

2 -"Would it be possible for someone to be human and have a different number of chromosomes?"

Absolutely, this is a well documented condition, generally called aneuploidy. 'Ploidy' is the fancy term for chromosome copy number.

Down syndrome, AKA "Trisomy 21" is probably the most well known example of this. Sufferers are very definitely still human. As the scientific name implies, they have 3 copies (so 1 additional) of chromosome 21. It is also possible to be lacking chromosomes, as well as having additional copies (for example, Turner Syndrome.

3 - "Does all DNA fingerprinting appear as bar codes and mean nothing until compared to a sample?"

Generally yes, you'd compare 2 samples to obtain an answer. You perform fingerprinting and sequence length polymorphism studies on your 'subject' sample, and on your 'reference' sample, and if they have the same banding pattern, you have a match. It will still contain information though. Those samples could be sent for sequencing for instance, which would tell you to even greater resolution, how similar 2 samples are.

EDIT

Just as a final thought (though getting a bit off the scope of the SE), if you did want the authorities to be able to tell that someone had been genetically modified, you could propose that those microsatellites are changed to something non-repetitive, which would potentially stand out. Or go even further and 'watermark' the genome, much like Venter et. al did, with the first synthetic genome (they incorporated a code to spell out messages in 'junk' regions of the genome).

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