Escape backticks
Use four spaces before your code?
List`1
Or use double backticks: ``List`1``
produces List`1
.
See http://daringfireball.net/projects/markdown/syntax, linked to from the formatting question box.
Note: Extra spacing will be necessary if you want to have a backtick at the end of your code, e.g., foo`
. This will keep it from consuming the first 2 closing backticks instead of the final two closing backticks.