Tough Interview Question – Help Please

Why are you leaving your current position? The real reason vs. what you should say

At the core of why I want to leave is the fact that my boss is a micromanaging jerk who has alienated everyone on the team. In fact, four employees have quit within the past year for that very reason. I am one of the last few looking to get out.

How should I handle this question in a job interview: ?why are you leaving your current position??