Can a graduate student join a fraternity?

[orca]

Hello all, I'm new here so sorry if this is in the wrong place. I have a question about fraternities though.

I am wondering if it is possible for a graduate student to join one? I am coming to the end of my undergraduate at a university in the UK (I am English) and one of my regrets is that I didn't think about going to college in the US and joining a fraternity.

I am looking to study an MS in something along the lines of biology/biotechnology/biochemical engineering. I have found a good looking one at John Hopkins, and the university also has Greek Life; however, I would feel silly applying and going there to find out that I can't rush (do frats rush or is it just sororities?)

I am gathering that whether a graduate student can rush or not is based a lot on the individual universities and Greek Life organisations, but how can I find this out for each and every fraternity at each and every university etc? Is there a general rule?

Thank you in advance.