If you are serious about building your glutes, quads and hamstrings, Google "Smolov squat routine" and go do it. It is one of the most proven and effective programs for adding muscle mass between your belly button and your knees. Also google "surviving Smolov" for some extra pointers.
If you want a bigger more muscular ass, squat ATG (ass to grass) with this program and you will get it. You will also get a really strong core, quads and hamstrings.
I'm in the Smolov program now, doing it ATG this time (first time I did it to parallel, got my squats to 405 which is decent for an old man)... it starts off easy, gets hard, gives you a 2 week deload, and then it tries to kill you. Totally worth it though. Squat gains between 50 and 130 lbs have been reported. You will need to eat A LOT in order to recover.