And with PCR, if you do it well, you can find almost anything in anybody. It starts making you believe in the sort of Buddhist notion that everything is contained in everything else. If you can amplify one single molecule up to something that you can really measure, which PCR can do, then there is just very few molecules that you don’t have at least one single one of in your body. So that could be thought of as a misuse of it – to claim that it's meaningful.
It (i.e. PCR) allows you to take a very miniscule amount of anything and make it measurable, and then talk about it in meetings and stuff like it is important.
PCR is just a process that's used to make a whole lot of something out of something. It doesn’t tell you that you're sick and it doesn't tell you that the thing you ended up with, really was going to hurt you or anything like that.
— Kary Mullis, Inventor of the PCR Test, 1993 Nobel Laureate in Chemistry
I must have said it a septillion times already but here's one more:
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