It doesn't effect men, but they are carriers.
How can they know this? In my opinion, there is no more reason to scientifically say something like the above than there is to say "there is no cure for colitis other than surgery." For the latter, maybe there is no cure NOW, and also, surgery doesn't sound like it is always quite a "cure," other than perhaps by definition.
Diagnosed with Ulcerative Colitis 6/2006 at age 26 after sudden E.R. visit