I am one of those using microblogging to share and receive pointers toward good articles/videos.
Here is an interesting trilogy: essential genes suffer from less mutations than other sections of the genome, Jon Perry describes a proposed mechanism that would explain why
https://www.youtube.com/watch?v=rLGam7Lx1Z4
https://www.youtube.com/watch?v=sXXH71rQRKo
https://www.youtube.com/watch?v=9OZ3JKtOU1k