Non-agency lenders that plan to originate qualified mortgages suggest that one of their top concerns is meeting the debt-to-income ratio requirements. Only non-agency mortgages will have to have a back-end DTI ratio of 43 percent or below to be classified as qualified mortgages under the Consumer Financial Protection Bureau rule taking effect Jan 10. Average DTI ratios on mortgages in jumbo mortgage-backed securities are well below that limit – 34.0 percent on the latest deal from Redwood Trust ...