How they determine Osama bin Laden really is Osama bin Laden:
Once samples from all sources are in hand, analysts isolate a bit of DNA from each sample, make lots of copies of it, and then process the copies through a machine that analyzes genetic markers — DNA fingerprints — that have been passed down through a subject’s family. Typically, Bieber said, DNA tests examine around 15 of these markers.
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It typically takes several hours to complete each step of the analysis process, Bieber said, though he noted that in high-profile cases like this one, law enforcement agencies might already have genetic profiles of the relatives available — which means they’d only have to complete one additional test.
I checked and it seems that there are paternity testing outfits that offer one day turnaround. So I guess it’s not implausible that they could have pulled this off. I assume they still use variable number tandem repeats for DNA profiling?
Update: Yeah, short tandem repeats.