Psychopathy And Gender

The brain anatomy associated with psychopathy is different in boys than it is in girls.

[I]n typically-developing boys, the volume of the anterior insula -- a brain region implicated in recognizing emotions in others and empathy -- is larger in those with higher levels of callous-unemotional traits. This variation in brain structure was only seen in boys, but not in girls with the same personality traits.

From here.