Star Trek has always had problems with GLBT characters

I've always found that aspect so disappointing. Once I read a really disturbing but well written fanfiction story which posits that the reason there is no gay characters in that universe is because they have developed a way to correct the 'disability' through eugenics, it was very creepy. But in the Trek shiny vision of the future, where everything sometimes seems a bit perfect, I've never been able to get that story out of my head. *cue twilight zone music*