Thanks to everybody!
I applied to mol biol, but from what I've read the School is not composed by depts., rather by labs. So, you don't need to apply for a specific subject, you can just choose what's more appropriate for your studies, I'd like to do cell/mol biology and bioinformatics.
I applied by the early deadline (December 1), the final one was January 1, and received the admission package some days before Christmas, that was an excellent personal present!
I have received other offers for interviews, but since the Rockefeller was my first choice and they offered the admission (at least this is what was written in the letter they sent), I declined the other offers. The others sent me e-mails. I live in Italy, maybethey call other applicants if living in the USA.