> The immune system is a giant random number generator. Your body randomly generates antibody patterns in the womb, so everyone is different. I read about this

> The immune system is a giant random number generator. Your body randomly generates antibody patterns in the womb, so everyone is different. I read about this in the book "Immune" [0], and it blew my mind. I just want to call attention to this part of your comment because people might breeze past it. Your immune system is tasked with what might seem an impossible problem: be able to kill anything that doesn't match "you" / your genome. But it can't encode everything that isn't "you" in the DNA that your immune system came from, partly because DNA transcription is generative: any arbitrarily-long sequence of codons creates a protein. So rather than try to write down all the things that could kill you (even ones that have never been encountered in all of human history) and remember how to kill those things, it generates random proteins, checks whether they look like you, and if they don't, figures out how to bind to those and produces proteins (antibodies) that bind to those things. (I'm heavily paraphrasing and I don't have the book handy to refer to, sorry) [0] https://www.amazon.com/Immune-Journey-Mysterious-System-Keeps/dp/0593241312 https://www.amazon.com/Immune-Journey-Mysterious-System-Keep...