How "random" are random primers?

[mdcabl at cc.newcastle.edu.au]

Hi all,

A friend of mine asked an interesting question.  What is the G-C content of a
random hexamer?  Before you flame, I know that it would be 50% if it is 
truly random sequence.  The more relevant question is perhaps is a random
hexamer truly random or is the G-C content decreased to increase the annealing
temperature of the hexamer.  My friend had no luck with the local tech-reps. 
Can someone out there help my friend out?

Cheers,
Allen Black
Dept. of Pathology
Univ. of Newcastle
mdcabl at cc.newcastle.edu.au