I did the tutorial and researched one pet fully fine, but after I've collected some vermillion exploring and try to research one gene, the bar is grey-d out and I can't click it. Did I miss something in the tutorial/FAQ?

Is your pet not Active? I think if it's busy doing something (questing, pregnant, etc) you can't do any research with it.

The pet you're attempting to research on must have energy in order to carry out the research. If your pet does have energy and you're still unable to do any research, then there may be a glitch. However, if the pet does not have any energy, you cannot research. I'm not sure on the technical aspect, but I believe 1 point of energy allows you to research 1 gene. I'll be studying this further unless it's confirmed by someone else

Edit:

It's possible that pets that are busy cannot have their genes researched.

Just checked that Kolibri and even though my pet Orange has 0 energy, he can still have his genes researched.

My mistake may have been because I was exploring with the pet, while at the same time I was checking it's researchablity. It does appear that if a creature is busy, the genes cannot be researched, as opposed to being based on energy. I was toying with this all day today with different pets and now that you mention that, checking again while not exploring does allow me to research with no energy. Apologies.