One aspect of the news regarding Osama Bin Laden was the rapid DNA match that confirmed his identity. Kit Eaton at Fast Company magazine takes a look at ‘DNA matching‘ and how it was used by the military.
DNA matching (also known as genetic fingerprinting) is different to full DNA sequencing–a long drawn out process that takes time, technology, and money to work out the absolute list of hundreds of millions of nucleotides, the famous G, T, C, A pattern that make up your genetic identity. Over 99.9% of everyone’s DNA sequence is the same, but that still leaves millions of bits of code that are unique to you. You share some of this unique code with your parents and siblings (and actually all of it if you’re an identical twin), but most of it is yours and yours alone–and this is where DNA matching works. It involves breaking your DNA down in a number of different ways and looking for a short list of what’s called loci–tell-tale markers that reveal where specific genes are located. The list from a test sample (from, say, a crime scene) is compared against the list from a reference sample obtained from your person–if the lists match, there’s an incredibly high statistical probability that the two DNA samples come from the same person…
Typical lab-based DNA matching tests like this can take up to 14 days; they’re painstaking and need to be repeated several times to ensure the sample’s not contaminated from any other DNA sources. But that’s not necessarily the only way to do these tests: Late in 2010, a University of Arizona team presented research on a machine that can do the analysis in just two hours in a largely automated way. It’s possible that knowing they were engaged on a mission to capture Bin Laden, U.S. Forces arranged for access to a machine like this to be on quick alert–probably for flying blood, cheek cells, and other samples taken from the body to the lab for expedited analysis.
