| Hi! My professional job is to write emulators, my wife is a molecular biologist, and as a kid I had dreams of writing the exact software you are referencing, so I think I have a decent handle on this question. We are no where close. We are ludicrously far away. Let's define the exact scenario: we want to replace clinical trials with a software simulation of the human body. If the simulation shows ill side-effects, we can deny approval of a treatment. 1. We can barely emulate other computers. It's tempting to look at something like a Nintendo emulator and think "oh this isn't that hard" but it is. Most video game emulators get about 90% of the emulation right and it's good enough for most games. But a common practice is to carry patches for all the software to patch the software. Hilariously, this is sometimes because the software is working around a hardware quirk or bug, but then it turns out difficult to emulate that quirk or bug, so we patch out the hack. If you want a perfect emulator it's really hard [0] If you're testing for bad drug interactions in a human simulation, it's exactly these quirks/bugs you want to accurately simulate! 2. The software of cells is DNA and the genes contained within. And genes encode for proteins which are amazing at doing a huge amount of varied tasks. But these are the basic building blocks, and we've only begun to scratch the surface. We made huge progress but we barely understand. [1] Imagine trying to work on an emulator of a microchip, but we don't quite understand how transistors work. 3. There's mind-body feedback loop with the endocrine system [2]. On top of everything else, we need to simulate the brain. Sure we can use a simplified model of that, but animal models are also simplification. The whole point was to try to get more accurate, and how accurate do you need to guarantee results? I know this argument is a bit absurd but it's to point out there's no finish-line, only more and more difficultly as higher accuracy is demanded. 4. How would we develop this simulator. Let's suppose I have my initial prototype. I've simulated various known drugs and got results, and I've tuned my parameters. But this is a massive complex system. Once I run a new novel drug, the point is that it's doing something new! So, if I have a bad reaction, is it a bad drug, or a simulation bug? Each scenario is new and poses to surface incorrect modeling between complex subsystems. You can argue that we'd build our confidence over time, but that means we'll see the long path to simulator development. There have been some attempts but they have appeared to not provide predictive results [3] 5. When asked to debate whether or not we could simulate the human body, the pro-simulation side invoked fantasy: "Exascale or quantum computing will enable algorithms that we are yet to conceive of" suggesting that we are very far away if it is possible. [4] [0] https://arstechnica.com/gaming/2011/08/accuracy-takes-power-... [1] https://www.quantamagazine.org/how-ai-revolutionized-protein... [2] https://www.psychologytoday.com/us/blog/the-brain-body-conne... [3] https://en.wikipedia.org/wiki/Virtual_Physiological_Human [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8638236/ |
And there are software approaches for humans like this one:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7285886/