The guys from CSI would be proud.

Investigators pulled DNA from a suspect’s cigarette butt and busted him for an August home invasion in Brooklyn, authorities said yesterday.

Paul Gaity, 23, was released after being questioned on an unspecified criminal case at a Brooklyn station house in September, sources said.

Police tested his cigarette and got a DNA match with a cap found in an alley near the scene of the Aug. 23 burglary on Beverly Road in Kensington, sources said. He was arrested Tuesday.