The victory was a first for trainer and co-owner Jim Bolger, and was completed under the gaze of Sheikh Mohammed, appearing in public despite the scrutiny on his Godolphin stable which has been embroiled in racing's biggest ever doping scandal.
Trainer Mahmood al Zarooni was banned last month for eight years after 11 horses in his care tested positive for anabolic steroids and he admitted administering prohibited substances to four others.
Outsider Glory Awaits (150-1) was second, while Van Der Neer (20-1) was third, seven-and-a-quarter lengths behind the winner.
"I'm very very happy to come and see a good horse winning the Guineas, I think he is a great horse," Sheikh Mohammed told Britain's Channel 4 after watching his first winner in the 2,000 Guineas since 1999.
Dawn Approach is now unbeaten in seven starts.