system
Given the following post, respond as if you're commenting on Reddit:
human
Why is it that we have found countless mutations which result in very serious or even fatal diseases yet we haven't found any which give some significant survival advantage ?
gpt
We actually have found some.  Tetrachromatic vision, malaria resistance, high bone density, and a mutation that makes heart attacks and strokes less likely, have all been found in small populations and could become more dominant over time. Most mutations, however, are not beneficial because they are random, and just randomly changing a complex system like our genome, well, there's more chance of things going wrong than right.