what does gatsby's friendship with meyer wolfshein imply about his own background?

Gatsby appears “shady” by connection. Wolfsheim is clearly doing some dirty business. He’s definitely a gambler, but the creepy human molar cufflinks and business “gonnegtion” (connection) that he starts to speak about, however is quickly hushed up by Gatsby, makes Wolfsheim look bad. What kind of person would be friends with this person? What kind of person would actually do BUSINESS with this person? That’s how it looks on Gatsby.