Row level security in PostgreSQL for different groups

Need a little help with row-level security in Postgres. I have several tables and three group roles: - group1 - group2 - group3 I have several login roles (users) that are members of each group, while "admins" are members of all groups. i.e. - group1 - user1_1 - user1_2 - group2 - user2_1 - user2_2 - group3 - user3_1 - user3_2 I would like to enable row-level security such that members of group1 can only see rows that were created by them or another user in group1 and same for group2 and group3. I can easily do this for individual users by creating a row that contains current_user and using something like:

CREATE POLICY row_policy 
    ON table1 
    USING (true) 
    WITH CHECK (created_by = current_user);

But how does one enable this for different group roles so that every member of that group has the same row-level privileges?