How to cascade information like the user roles ?

Hi,

I need something like the user-roles of PG to store options of my users.
I guess i need a table with roles, options and one that stores the
refernces from roles to options.

roles (role_id, role_name)
option (option_id, option_name)
role_has_option (role_fk, option_fk)

so far is easy. Now I can let role1 have option1 and option2 ...

But I'd further like to let role2 inherit role1's options and also have
option3.
role_inherits_role (parent_role_fk, child_role_fk)
1, 2

What SELECT would deliver all options for role2 inkluding the inherited
ones?
like
role_id, option_id
2, 1
2, 2
2, 3