Having done some reading for my referral statement, HM is 1:5000, and there are 2 views on HMS 1:150,000 and 1:300,000, which one is acurate I don't know, but the 1:150,000 was a study done in the UK not so long ago, and they found 4 families displaying symptoms, so that's where the figure came from, can't remember where it was though.
Whether the 1:300,000 relates to world population I don't know, so even with the lower figure, it is still quite rare.
Hope that answers the question,
Professional Hypochondriac and Attention Seeking mother! Familial JHS/EDS3, F/M, 22/3/2010
Skake(Thats the Tremor) Rattle(That's the tablets) and Roll(in and out of anything) all the way.Hypermobile 2005