How can I prepare myself and what kind of questions can I expect? What topics should I prepare for my bioinformatics PhD admissions interview apart from my previous research?
What are the committee members looking for? What questions should I be prepared with?
What should/can I ask them?
Seriously, this is better suited for academics.stackexchange, where it is discussed a lot (on-topic): http://academia.stackexchange.com/search?q=phd+interview
Is this an interview for a specific PhD in a specific group, or is it for entry onto a generic PhD programme where you'll choose your group later?
I believe its a generic PhD program interview! Though there is a possibility that the interviewer turns out to be the one in whose lab I've expressed my interested during my applications.
If you've expressed an interest in an individual, they'll try to put them on your panel - make sure you know what they do and why you're keen on them.
What is your favorite question to ask when interviewing potential Bioinformaticians?
PhD candidate interview questions for a mixed lab/bioinformatics project