Well this is disappointing.
Someone sent me an announcement for SynBioBeta SF 2016 - SynBioBeta possibly thinking I would go to it. Since it was local I decided to check it out. And, well, the 1st thing I did was to look at the gender balance of the speakers (as much as I could infer from a quick skim). And it did not look good. So I dug into it in more detail.
They have a speaker page and I went through most of them to make sure my inference of gender was correct (based on looking at the pronouns used to describe them in their speaker bio and also in other web sites). I know this is imperfect but seems potentially a decent estimator. And low an behold when you sum it all up you get 79% male speakers vs. 21% female speakers. They could definitely do better.