SilentC has reminded me of a bouncer incident.
Whilst entering a seedy establishment the bounce was giving the guy in front a hard time. You know the drill, he is going to let you in but wants to feel important. "Tuck your shirt in, not sure those shoes are appropriate etc".
Anyway the guy in front finally gets in and the bouncer starts to open his mouth to give me a hard time, when I said "hey mate you dropped a chromosome". While the muscle bound chap looked around on the ground for his missing chromosome I just walked in.
Don't know if he ever found it..........