According to Joe Pistone in his book, "The Way of the Wiseguy," now you only have to have an Italian (not necessarily Sicilian) father to be made.
BTW: While Masseria was a "Moustache Pete," some non-Sicilians were made during his era--Joe Valachi and Vito Genovese (Neapolitan) and Frank Costello (Calabrese). Capone's outfit was never a Mafia family.