I think ME/CFS is estimated to be approx 2/3 women and 1/3 men.
I think with Autism it's approximately reversed - 2/3 male and 1/3 female
I think I heard autism is 4:1 male:female, but the point still holds because autism seems likely to divide into genetic and post-80s epidemic (XMRV) forms. I speculated wildly around this point quite a while ago, here
and on an autism thread. News of the autism connection made a few of us suspicious of exactly this possibility - ie that autism and ME/CFS are two different forms of expression of XMRV, and that perhaps gender assumptions tend to lead to the difference in diagnosis. I also suggested that the 2:1 ratio seems suspicious to me (would be more suspicious if I knew that ratio is consistent in different countries, and averages very close to 2:1). Another possibility we discussed was possible differences due to transmission - eg if male to female transmission were possible but not the reverse. And finally, the really wild speculation bit was that in the prostate study, the infection rate in the male controls was 6%, whereas in WPI it was 4%, which if both figures were accurate would mean XMRV infection rate would be either 2:1 or 4:1 male:female (depending on whether the controls were gender-matched).
But I have to agree with Levi as well - I too suspect there are going to be lots of men appearing as if from nowhere and testing XMRV+. Unlike Levi, I do see a GP, but I had to switch a couple of times to find one who's prepared to operate on the basis that my condition is physical; any suggestion that it's psychological, and I'm off. I recall a frank discussion where my doc and I agreed that while a diagnosis of CFS would probably be technically correct, there was no useful purpose in that diagnosis because the only treatment available was CBT. So I effectively refused the diagnosis since by definition it was considered psychological, and my GPs were all wary of diagnosing that way because (a) it supposedly mainly affects women, (b) it could have negative repercussions for me to have that diagnosis as a man, and (c) it would close down the treatment options rather than open them up. The other man I know with CFS (or I should say CFS symptoms) prefers a diagnosis of MCS, and as far as I know he hasn't seen a mainstream doc for years.
So yes, I suspect there are a lot more of us out there...